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385 Cards in this Set

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Motor Behaviors Involve the Entirety of the CNS
Spinal Cord - protective reflexes, locomotion generator
Cerebellum - breathing, chewing, swallowing, eye movements
Cerebral Cortex - fine motor skills (speech, hand-finger control)
Brainstem
Basal ganglia - eating and drinking
Direct Motor Pathways
Nerve impulses for precise, voluntary movement
Three tracts: lateral corticospinal, corticobulbar, anterior corticospinal
Somatic = Voluntary = Skeletal Muscle
Motor Cortex: contains upper motor neurons
The primary motor area of the cerebral cortex is responsible for initiation of voluntary movements (area 4, precentral gyrus)
Spinal cord contains lower motor neurons
A.K.A - alpha motor neurons. These neurons actually connect to skeletal muscle
Spinal Cord
Dorsal (posterior) = sensory
Ventral (anterior) = motor

Outer Layer: white matter, fiber tract = axons and their myelin
Inner Layer: gray matter, neuronal cell bodies and dendrites
Ascending and Descending Motor Tracts
Ascending Sensory Tracts
Sensory
Afferent pathway - axons that conduct nerve impulses from the spinal cord toward the brain
Descending Motor Tracts
Motor
Efferent pathway - axons that carry nerve impulses away from the brain down the spinal cord
Direct Motor Pathway --> Path Taken
Motor Cortex --> Corona Radiata --> Internal Capsule --> Crus Cerebri (midbrain) --> Basal Pons (pons) --> Pyramids (Medulla Oblongata) --> Corticospinal Tracts (Lateral and Ventral - anterior) [spinal cord] --> Ventral Horn --> Ventral Roots --> Peripheral Nerves --> Skeletal Muscle
Premotor Cortex
think about moving
Primary Motor Cortex
actual movement
Upper Motor Neurons - essential for planning, initiating, and directing sequences of voluntary movement
Corona Radiata
Axon fibers exit the motor cortex using the this (use it for travel)
Condenses into internal capsule (V-shaped condensation of motor fibers)
Internal Capsule
3 Limbs
Anterior Limb (A) - sensory
Posterior Limb (P) - motor, trunk, and extremities (stroke = trunk)
Genu (g, bend) = motor, brain stem (if stroke occurs, trouble moving head and neck if this part is damaged)

5 total limbs of internal capsule, the other two are sensory
Corticonuclear Tracts (AKA - corticobulbar)
motor cortex to skeletal muscles of head and neck to coordinate precise, voluntary movements, travel in genu of internal capsule
Bulb = brain stem
Lower Motor Neurons = motor nuclei of cranial nerves III, IV, V, VI, VII, IX, XI, and XII

Discrete voluntary (somatic) movement of muscles of neck, larynx, tongue, head and face
Axons travel through corona radiata, genu of the internal capsule and crus cerebri
Axons cross midline at the level of the motor nucleus they innervate (lower motor neurons, no discrete decussations)
Innervate head and neck muscles via the cranial nerves
Unlike spinal cord, innervation is often bilateral
Crus Cerebri
continuation of the posterior limb of the internal capsule
Located in the midbrain
Goes to the basal pons (located in the pons) to the medulla oblongata where it enters the pyramids
Pyramids
Defines the border between the spinal cord and the medulla oblongata
Pyramidal Decussation defines the transition between the brainstem and the spinal cord
3/4 of the axons cross the midline
Lateral Corticospinal Tracts
Motor cortex to skeletal muscles of the OPPOSITE side of the body
Precise, voluntary movements of the arms and legs (distal part of free limbs)
Right side of the brain controls the left side of the body
Fibers cross at PYRAMIDAL DECUSSATION
Anterior (Ventral) Corticospinal Tracts
Motor cortex to skeletal muscles of both sides of the body
Responsible for trunk movements
Half side of the cords cross
Approximately half of the fibers cross at the PYRAMIDAL DECUSSATION and half do not
Synapse in the ventral horn (alpha motor neurons)
Alpha motor neurons project their axons via the ventral roots
Indirect Motor Pathways
Provide input to lower motor neurons from motor cortex to motor centers in the brainstem
4 Descending Pathways
Vestibulospinal Tracts: ORIGINATE: vestibular nuclei, pons, and medulla and INSERT in the
Reticulospinal Tracts: reticular formation found throughout brain stem
Tectospinal Tract: superior colliculi, midbrain
Rubrospinal Tract: red nucleus, midbrain
Medial and Lateral Vestibulospinal Tracts
Vestibular nuclei, pons, and medulla
Inner ear information
Tells the person where they are in space
Reflexive regulation of balance and posture
Originate in vestibular nuclei
Medial Vestibulospinal Tracts
descend bilaterally through cervical segments of spinal cord and influences neck musculature
Lateral Vestibulospinal Tract
descends to lumbar-sacral segments of spinal cord
Reticulospinal Tracts
Origin: reticular formation found throughout brain stem (specifically pons and medulla)
Functions to set muscle tone (adjust posture) in anticipation of a movement
Found at all levels of the spinal cord - would be a lot slower without it
Tectospinal Tract
mediates reflexive movement of head and neck in response to sensory stimuli (predominantly vision and hearing)
Originates in the superior colliculus (SC, midbrain) and descends through cervical levels of the spinal cord
Rubrospinal Tract
Midbrain of brain stem
Regulates muscle tone in upper limbs
Ex. putting hands out when falling
Originates in red nucleus (R) of the midbrain then crosses at the level of the nucleus
Descends through cervical spinal cord, following a pattern similar to the corticospinal tract
Nuclei Include:
Caudate Nucleus and Putamen --> Striatum
Globus Pallidus --> Pallidum
Substantia Nigra --> Brain Stem
Subthalamic Nucleus --> Diencephalon
Basal Nuclei
collection of interconnected subcortical nuclei that function as a central link in the part of the motor system that translates the desire to move (mentation, i.e. thinking) into action
"Organ of Habit"

"Selects" desired behaviors and "inhibits" unwanted behaviors (unwanted = trimmers)
They remember/involved in habits
Basal Nuclei - Frontal Plane
Basal Nuclei - Frontal Plane
Basal Nuclei - Loop
Works in a loop:

The cortex projects to the striatum (caudate and putamen) which projects to the golubus pallidus and the substantia nigra. The substantia nigra projects back to the striatum
Cerebellum
maintains proper posture and balance and is activate in learning and performing rapid, coordinated highly skilled movements

Each cerebellar hemisphere influences movements on the ipsilateral (same) half of the body
How does the Cerebellum Work?
Monitors intentions for movement by receiving impulses from the motor cortex and basal nuclei via the pontine nuclei
Monitors actual movement by receiving input from proprioceptors in joints and muscles that reveal what is actually happening
Compares the command signals with sensory information
If there is a discrepancy between intended and actual movement, sends out corrective feedback to upper motor neurons
Cerebellum Anatomy
10% of the brain's mass, but contains 50% of the neurons
Consists of a cortex, underlying white matter and deep nuclei
Contains 5 different neuronal types
Is attached to the brain stem by 3 paired peduncles
sits in the posterior cranial fossa, beneath the tentorium cerebelli
The Cerebellar Peduncles
the cerebellum forms the roof of the 4th ventricle
The cerebellum is removed from the brain stem by cutting through the peduncles
Superior, middle, inferior cerebellar peduncle
Superior Cerebellar Peduncle
main outflow, fibers project to motor cortex
Middle Cerebellar Peduncle
fibers enter from the pons
Inferior Cerebellar Peduncle
fibers enter from the medulla and spinal cord
Superior Surface of the Cerebellum
Vermis (wormlike) - the midline region of the cerebellum
The hemispheres, left and right, are on either side of the vermis
Vermis (wormlike) - the midline region of the cerebellum
The hemispheres, left and right, are on either side of the vermis
Inferior Surface of the Cerebellum
Tonsils - lobules of the hemisphere that lie above the foramen magnum
They may be herniated through the foramen magnum by increased intracranial pressure
This is bad, why? - increase pressure - herniate and die
Tonsils - lobules of the hemisphere that lie above the foramen magnum
They may be herniated through the foramen magnum by increased intracranial pressure
This is bad, why? - increase pressure - herniate and die
Cerebellar Cortex
Cerebellar Cortex
Folds = folia
Molecular layer - lots of connections, few neurons
Purkinje cell layer - projects to deep nuclei - cells are huge and dendrites are in 1 plane (flat)
Granula cell layer - lots of connection
Folds = folia
Molecular layer - lots of connections, few neurons
Purkinje cell layer - projects to deep nuclei - cells are huge and dendrites are in 1 plane (flat)
Granula cell layer - lots of connection
Deep Cerebellar Nuclei
out via the superior cerebellar peduncle
Purkinje cells communicate with this
Loss of Cerebellar Function
does not result in paralysis or inability to initiate movement. Rather cerebellar diseases produces disturbances in the coordination and fine control of movements and posture
Diseases of the Motor System (Cerebellum)
Parkinson's Disease
Huntington's Disease
ALS (upper and lower) - Lou Gehrig's Disease
Stroke
Brainstem
Brainstem
Midbrain
Pons
Medulla Oblongata
Midbrain
Pons
Medulla Oblongata
Medulla Oblongata
Transition from spinal cord to brainstem
Ventral Surface: Pyramid and Olivary eminence
Dorsal Surface: covered by cerebellum
Cranial Nerves: IX, X, XI, and XII
Pons
floor of fourth ventricle
Cranial Nerves V, VI, VII, and VIII
Ventral Surface of Midbrain
Crus cerebri, cranial nerves III and IV
Other landmarks: Optic chiasm, mammilary bodies, infundibular Stalk
Crus cerebri, cranial nerves III and IV
Other landmarks: Optic chiasm, mammilary bodies, infundibular Stalk
Dorsal Surface of Midbrain
Dorsal Surface of Midbrain
Dorsal Surface:
Tectum - superior and inferior colliculi (2 each), cerebral aqueduct, pineal gland
Olfactory (I) Nerve
Entirely sensory
Extends from olfactory mucosa of nasal cavity to olfactory bulb
Projects directly to limbic cortex
Sense of smell
Optic (II) Nerve
Entirely sensory
Carries signals from neural retina to thalamus
Half of the information crosses to the contralateral thalamus and cortex
Half project to ipsilateral thalamus and cortex
Crossing occurs at the optic chiasm
Conduct nerve impulse...
Entirely sensory
Carries signals from neural retina to thalamus
Half of the information crosses to the contralateral thalamus and cortex
Half project to ipsilateral thalamus and cortex
Crossing occurs at the optic chiasm
Conduct nerve impulses for vision
In sequence, visual signals are relayed from rods and cones to bipolar cells to ganglion cells
Oculomotor (III) Nerve
Innervates extrinsic muscles of the eye
Levator palpebrae - raises eyelid (loss = ptosis) - could be somatic
Somatic - 4 extrinsic eye muscles

Parasympathetic (visceral) - 2 intrinsic eye muscles
Ciliary muscle and sphincter pupillae - these muscles allow for accommodation for near vision (changes shape of lens during reading) - constriction of pupil
Trochlear (IV) Nerve
Somatic = 1 extrinsic eye muscle
Superior oblique eye muscle - loops around a bony hook = trochlea, hence it's name
Nerve wraps around the pons - comes up dorsally and wraps around (only one that does that)
Trigeminal (V) Nerve
Motor and sensory
Motor: muscles of mastication
Sensory: face and oral cavity
3 Branches:
Ophthalmic - sensory
Maxillary - sensory
Mandibular - sensory and motor
Abducens (VI) Nerve
Motor
Somatic - 1 extrinsic eye muscle - lateral rectus: abducts the eye (lateral rotation)
Facial (VII) Nerve
Motor (somatic) - muscles of facial expression
Parasympathetic (visceral) - salivary glands, nasal and oral mucosa, lacrimal glands

Sensory: taste, anterior 2/3's of the tongue
Vestibulocochlear (VIII) Nerve
Cochlear branch: carries auditory information from cochlea
Vestibular branch: carries information concerning blance from the vestibular apparatus and semicircular canals
Gloosopharyngeal (IX) Nerve
Motor (somatic) Stylopharyngeus muscle (lifts throat during swallowing)
Parasympathetic - parotid gland (secretes saliva)

Sensory - sensation and taste posterior 1/3 of tongue
Vagus (X) Nerve
Sensory and motor
Motor: parasympathetic to thoracic and abdominal viscera, innervates gut to the splenic flexure
Sensory: same distribution as motor - convey sensations such as hunger, fullness, and discomfort from thoracic and abdominal organs
Accessory (XI) Nerve
Motor: somatic (voluntary)
Cranial portion arises in the medulla and innervates skeletal muscle of the larynx and soft palate
Spinal portion arises in the cervical spinal cord and innervates the sternoclediomastoid and trapezius muscles
Motor: somatic (voluntary)
Cranial portion arises in the medulla and innervates skeletal muscle of the larynx and soft palate
Spinal portion arises in the cervical spinal cord and innervates the sternoclediomastoid and trapezius muscles
Hypoglossal (XII) Nerve
Motor: somatic
Intrinsic muscles of the tongue
Lower Motor Neurons
alpha motor neurons that extend out of the brain stem and spinal cord to innervate skeletal muscles in the head and body - provide output from the CNS to skeletal muscle fibers
Upper Motor Neurons
essential for planning, initiating, and directing sequences of voluntary movements
Cardiovascular System
Blood, heart, and blood vessels
Interstitial Fluid
Single-cell systems - do not have cardiovascular system
Blood
matrix with connective tissue - blood's matrix is plasma (fully fluid)
Cellular component - maintains the matrix
Interstitial Fluid
surrounds a body of cells
nutrients and waste move between the blood and the interstitial fluid and from there the interstitial fluid and the internal cell
Want to move nutrients through interstitial fluid
Hematology
study of blood, blood-forming tissues, and their disorders
Functions of Blood
Transportation
- Gases, nutrients, wastes, hormones
Regulation
- pH, temperature, water balance
Protection
- Clotting, immune
Physical Properties of Blood
"thicker" than water - high viscosity
38 degrees C (100.4 F)
pH: 7.35 - 7.45 ********
Color: red (oxygenated) <--> purple (deoxygenated)
Typically 8% total body weight
Volume:
Men - 5-6 liters (1.5 gal)
Women - 4-5 liters (1.2 gal)
Blood Components
Blood plasma (55%) - top layer
   - Water (and solutes)
   - Proteins 
          - Albumins, globulins, fibrinogens, immunoglobulins
Formed Elements (45%) - bottom layer
      - Leukocytes (WBC's)
      - Thrombocytes (platelets)
      - Er...
Blood plasma (55%) - top layer
- Water (and solutes)
- Proteins
- Albumins, globulins, fibrinogens, immunoglobulins
Formed Elements (45%) - bottom layer
- Leukocytes (WBC's)
- Thrombocytes (platelets)
- Erythrocytes (RBC's) - very bottom layer

Middle layer during centrifusion has DNA
Albumins
smallest and most numerous of proteins
Responsible for colloid osmotic pressure; major contributors to help blood viscosity; transport hormones (steroid), fatty acids, and calcium; help regulate blood pH
Different from other proteins because they are not glyclocylated - carbohydrates don't readily attach to them - all other blood proteins are glyclocylated
Globulins
large protein - plasma cells produce immunoglobulins (gamma globulins)
Immunoglobulins help attack viruses and bacteria; alpha and beta globulins transport iron, lipids, and fat-soluble vitamins
Fibrinogen
Large protein
Plays essential role in blood clotting
Formed Elements of Blood
White Blood Cells
Red Blood Cells
Platelet
Blood Smear
Cheap and fast way to see what might be going on in respect to the blood
Looking for how dense the blood cells are (not very dense - anemia)
Lots of white blood cells when we are sick
Also can see thrombocytes (platelets)
Hematocrit
Percentage of red blood cells of total blood volume
Males: 40-54% - have higher hermatocrit
Females 38-46%
Anemia
Low hermatocrit - cannot supply tissues with oxygen that they need
Reduced oxygen carrying capacity of blood
Iron-Deficiency Anemia - inadequate iron in diet
Megaloblastic Anemia - inadequate vitamin B12 intake
Pernicious Anemia (stomach no intrinsic factor) - parietal cells in your stomach are attacked by your immune system - will not secrete intrinsic factor which is necessary for the uptake of B12
Hemolytic Anemia - plasmalemma rupture
Thalassemia - large contributing factor to anemia
Aplastic Anemia (red bone marrow destruction - destruction of hermatopoeitic connective tissue
Polycythemia
high increase in the percentage of RBC's - high hematocrit (above 54%)
Can be caused by dehydration or blood doping in athletes
Erythropoietin (EPO)
Direct stimulus for the production of red blood cells is hypoxia (cellular oxygen deficiency) in kidney cells
Stimulates the synthesis of EPO in the kidneys
EPO stimulates the production of RBC's
Growth factor for erythrocytes
Kidneys (peritubular interstitial cells - fibroblasts)
Liver (perisinusoidal cells) during fetal development
10 mU/ml --> 10,000 mU/ml
Blood Cell Formation
Hemopoiesis - process by which the formed elements of blood develop
First occurs before birth in the yolk sac of an embryo and later in the liver, spleen, thymus, and lymph nodes of a fetus.
In the last three months before birth, red bone marrow becomes the primary site of hemopoiesis and continues to be the source of blood cells after birth and throughout life
Red Bone Marrow
highly vascularized connective tissue located in the microscopic spaces between trabeculae of spongy bone tissue
about .05-.1% of red bone marrow cells are pluripotent stem cells - capable of developing into many different types of cells
Pluripotent Stem Cells
differentiate into myeloid stem cells and lymphoid stem cells
differentiate into myeloid stem cells and lymphoid stem cells
Myeloid Stem Cells
give rise to erythrocytes, thrombocytes, granular leukocytes (neutrophils, eosinophils, basophils), mast cells, and monocytes
Complete their development in red bone marrow
Lymphoid Stem Cells
gives rise to agranular leukocytes (minus monocytes)
(T lymphocytes, B lymphocytes, natural killer cells)
Begin to develop in red bone marrow but complete development in lymphatic tissues
Myeloid and Lymphoid Cells and Hemopoiesis
Myeloid stem cells differentiate into progenitor cells - no longer able to reproduce themselves
CFU-E - produce erythrocytes (red blood cells)
CFU-Meg - produce megakaryocytes (the source of platelets)
CFU-GM - produce granulocytes (specifically neutrophils) and monocytes
In the next generation, develop into precursor cells - over several cell divisions they develop into the actual formed elements of blood

Lymphoid stem cells differentiate into T lymphoblast and B lymphoblasts which ultimately form T lymphocytes and B lymphocytes respectively
Hemopoietic Growth Factors
Cytokines
Erythropoeitin (EPO)
Thrombopoietin (TPO)
Other Cytokines
Cytokines
protein signaling molecules
Broad category of small peptide molecules - glyclocylated - means of communication among leukocytes and other cells of the body
Thrombopoietin (TPO)
Secreted by the liver to produce more thrombocytes
Other Cytokines
Colony stimulating factors
Interleukins
Bone Marrow Exam
in sampling for pathologies that might related to bone marrow (i.e. leukemia) - taken from the posterior iliac crest or the sternum
Relatively simple procedure but somewhat painful
Low risk of side effects
Red Blood Cells (Erythrocytes)
4.8 (females) - 5.4 (males) million RBC's/uL
Biconcave discs - more surface area
Hemoglobin (33% of weight) - 280 million molecules per RBC - transports it
Anucleate, lack mitochondria
Life cycle average = 120 days
Production = 2 million RBCs/second
Hemoglobin
Reversibly binds to oxygen
At the center of each sub-unit is a heme groupwhich has an iron as its center where oxygen can reversibly bind to it
Sickle Cell Disease (SCD)
Hb-S
Autosomal recessive - need to receive sickle cell allele from both parents
Overdominance
Malarial resistance
May be compounded with a thalassemia (fewer RBC's produced and less hemoglobin)
Predisposes hemoglobin molecules into forming polymers - quaternary structure changes and will form non-covalent polymer with hemoglobin molecules - RBC's take on a sickle-shape
When they sickle they become adherent to one another and this causes them to lose their elasticity and get stuck in capillaries causing a lack of blood flow (eskemia) and can be deadly
Hemoglobin
Globin protein - 4 polypeptides (2 alpha, 2 beta)
Heme - iron-containing pigment
Reversibly binds to O2 - oxygen picked up in the lungs - as blood flows through tissue capillaries, the iron-oxygen reaction reverses and hemoglobin releases oxygen which diffuses into the cells
Carrier 23% of CO2 - reversibly binds to carbon monoxide - competes and lowers the ability of hemoglobin to carry oxygen
May release NO (nitric oxide) - vasodialation - helps to control blood flow
Erythropoiesis
proerythroblast (red bone marrow) will divide and some of them will move from red bone marrow to blood system and will eject nuclei --> reticulocyte (ejected nucleus; in CVS) eventually matures --> mature erythrocyte
Blood Doping
Exogenous EPO
Transfusion (homologous or autologous) - inject exogenous EPO
Natural blood doping - training at higher altitudes - body increases the production of red blood cells
Polycythemia - abnormally high level of RBC's
Blood Group Systems
RBC surface antigens - can be used to distinguish types of blood cells
100 genetically identified, 14 recognized systems
Four basic blood types: Type A, B, AB, and O - named for surface feature antigens
Type A - has A antigen and anti-B antibody in the plasma
Type B - has B antigen and anti-A antibody in the plasma
Type AB has both A and B antigens and neither antibody
Type O has neither A or B antigens but has both anti-A and anti-B antigens in the plasma
Hemolytic Disease of the Newborn (HDN) - Rh+
Arises during pregnancy
If a small amount of Rh+ blood leaks from the fetus through the placenta into the bloodstream of an Rh- mother, the mother will start to make anti-Rh antibodies - usually affects second pregnancy
If the mother becomes pregnant again, her anti-Rh antibodies can cross the placenta and enter the bloodstream of the fetus
If the fetus is Rh- no problem (Rh- blood does not have the Rh antigen) - If the fetus is Rh+ agglutination (clumping) and hemolysis (rupture) of REBC's brought on by fetal-maternal incompatibility may occur in the fetal blood
Injection of anti-Rh antibodies (RhoGAM) can prevent HDN
White Blood Cells (Leukocytes)
Granular vs. Agranular
Granules are clusters of proteins
Agranular are usually lymphocytes themselves or phagocytic
Monocytes fall under agranular but come from lymphoid stem cell*****
Phagocytosis - ingest bacteria and dispose of dead matter
Emigration (formly diapedesis) - able to cross capillary walls
Chemotaxis
Major histocompatibility complex (MHC) antigens
Granular Leukocytes
Neutrophils
Eosinophils
Basophils
Neutrophils
no strong dye attraction - stain dull blue/pink
2-5+ lobed nuclei - older the cell, more nuclei
Polymorphonuclear leukocytes - "polys" - lots of nuclei
Most abundant, first on scene
Phagocytic, chemotaxic, release cytokines
Degranulation - release a lot of different substances like defensins and cytokines which disrupt cell membranes of various pathogens
Eosinophils
Absorb eosin stain (acidic) - red-orange
2-3 lobed nuclei
Granules do not obscure nuclei
Phagocytic, chemotaxic
Degranulation (enzymes)
Numbers are greatest during parasitic infestation (allergies and endoparasites)
Basophils
Absorb basic stain - blue-purple
2-lobed nuclei
Granules obscure nuclei
Least common
Chemotaxic
Allergies and ectoparasites
Degranulation - generally releasing substances that are going to compliment the immune system (histamine, heparin, serotonin, etc.)
Agranular Leukocytes
Lymphocytes
Monocytes
Lymphocytes
Nuclei round or indented and stain dark
Cytoplasm stains blue
T cells
B cells --> plasma cells
Natural killer cells (innate)
Small vs. Large Lymphocytes
LL: acute viral infections and immunodeficiency diseases
Monocytes
U-shaped nuclei
Differentiate into macrophages (fixed of wandering) and dendritic cells
Both are phagocytic and antigen-presenters (they will engulf a pathogen, break it down, and move pieces of that pathogen to their surface and head to the lymphatic system where they'll meet up with cytotoxic t-cells or b-cells and present pathogen to them and body will become resistant to that particular pathogen)
Differential White Blood Count
Leukocytosis - higher than typical level WBC present
Leukopenia - lower than expected level of WBC's
Leukocytosis - higher than typical level WBC present
Leukopenia - lower than expected level of WBC's
Leukemia
bone marrow cancers with run-away abnormal leukocyte division
Acute lymphoblastic leukemia (ALL)
- Most common leukemia in children
Acute Myelogenous Leukemia (AML)
-Both adults and children
Chronic lymphoblastic Leukemia (CLL)
- Most common in adults (esp. 55+)
Chronic myelogenous leukemia (CML)
- Mostly in adults

Acute - generally runaway division of leukoblasts
Chronic - generally runaway division of leukocytes
Lymphoblastic - cells that are derived from lymphoid stem cells
Myelogenous - cells that are derived from the myeloid stem cells
Platelets (Thrombocytes)
Derived from myeloid stem cells
Megakaryocyte colony forming units --> megakaryoblasts --> megakaryocytes --> 2-3k thrombocytes
Important for blood clotting
Intrinsic and extrinsic cascades (clotting cascades) - prothrombin is converted into thrombin (which is an enzyme) which catalyzes two reactions: the first takes fibrinogen and converts it into fibrin (insoluble fibrinogen): it also catalyzes the formation of Factor 13A to Factor 13 - gets fibrin to clot - fibrin forms a dense web and thrombocytes get caught up in that web to form a blood clot
Stem Cell Tranplants
Bone Marrow
Destruction and replacement with donor tissue
Vulnerable to infection
Graft-vs.-host disease
Cord Blood
Easily obtained
Less infection and g-v-h issues
Stored indefinitely
Heart
pump driven by cardiac muscle tissue
Connective tissue
about the size of closed fist
Sits in the mediastinum - space between the sternum and the vertebral column and two lungs (also between 1st rib and diaphragm)
Medial to pleurae
Always working
Heart Surfaces and Borders
Heart is medial and posterior to the lungs- great vessels come superiorly off of the heart
inferior surface rests on the diaphragm
Left border more extensive than right border
Apex of the heart points anteroinferiorly (and slightly to the left)...
Heart is medial and posterior to the lungs- great vessels come superiorly off of the heart
inferior surface rests on the diaphragm
Left border more extensive than right border
Apex of the heart points anteroinferiorly (and slightly to the left)
Anterior surfaces and posterior surfaces (against the vertebral column)
Pericarium
Fibrous pericardium
Serous pericardium
Fibrous Pericardium
Dense irregular connective tissue (inelastic)
protective, anchor
most external layer
Serous Pericardium
Parietal layer- fused to the fibrous pericardium
Pericardial cavity (percardial fluid - lubricant)
Visceral layer (epicardium) - adherant to the heart
Pericarditis
Acute
Typically suddenly and idiopathic (don't know what causes it)
May mimic "heart attack" symptoms
Treated with NSAIDs
Chronic
Gradual and long-lasting
May lead to cardiac tamponade (when there is too much fluid in the serous layers)
Treated with pericardiocentesis - use need and angle it upward and aspirate until we draw fluid
Layers of the Heart
Visceral Pericardium (Epicardium) - lays over a little bit of adipose tissue and vasculature
Myocardium - comprised of cardiac muscle tissue
Endocardium - deepest layer of the heart and is made up of mesothelium

All of the cardiovascular system has simple squamous with basement membrane
Epicardium
Two layers:
Visceral serous pericardium (mesothelial)
Fibroelastic and adipose
Neurovasculature for myocardium
Myocardium
Cardiac muscle tissue - responsible for the pumping action of the heart
Myocarditis - inflammation of the myocardium that usually occurs as a complication of a bacterial or viral infection
Endocardium
Endothelial
provides a smooth lining for the chambers of the heart and covers the valves of the heart
Endocarditis - inflammation of the endocardium from bacteria - can affect valves of the heart and how it functions
Cardiac Muscle Tissue
Striated - relies upon the overlap of motor proteins (actin and myosin) to work
Only has one nucleus per cell
Intercalated Discs - this is where muscle cells connect to each other - embedded within the membrane are desmesomes (anchor adjacent ce...
Striated - relies upon the overlap of motor proteins (actin and myosin) to work
Only has one nucleus per cell
Intercalated Discs - this is where muscle cells connect to each other - embedded within the membrane are desmesomes (anchor adjacent cells together) and gap junctions (tubes that can continuously connect adjacent cells that share a cytoplasm)
Adjacent cardiac muscle cells are able to work in concert because they share cytoplasm - as one cell is depolarized the cytoplasm allow all the other cells to contract as well
Cardiac Muscle Cell
Can be autorhythmic - important to how the heart functions
Can be autorhythmic - important to how the heart functions
Circulations of the Heart
Systemic Pump - comes from the left side of the heart - works through aorta - circulates oxygenated blood to all the systems of the body
Pulmonary Pump - comes from right side of the heart - fed by pulmonary artery - moves deoxygenated blood through the blood vessels of the lungs
Coronary - provides myocardium with energy and nutrients it needs to make that energy - comes from right side of the heart
Surface Features of the Heart
Auricles
Anterior Interventricular Sulcus
Posterior Interventricular Sulcus
Coronary Sulcus
Auricles
expansions of the atria that allow blood to flow into it (hold a greater volume of blood)
Anterior Interventricular Sulcus
shallow groove on the anterior surface that marks the external boundary between the right and left ventricles
Posterior Interventricular Sulcus
marks the external boundary between the ventricles and the posterior aspect of the heart
Coronary Sulcus
goes around the heart - separates superior atria and inferior ventricles - coronary arteries are named for occupying the coronary sulcus
Structure of Heart
Atria
Atrioventricular Valves
Ventricles
Semilunar Valves
Atria
gets deoxygenated blood from the vena cava (superior and inferior) and coronary sinus
walls of the atria are muscular but thin
Pectinate Muscles - parallel ridges that line the remainder of the atrial wall
Atrioventricular Valves
Tricuspid Valve
Bicuspid (mitral) Valve
Chordae Tendineae - tendonlike cords - cusps of the tricuspid valve are connected by these
Ventricles
Left ventricle is thicker than the right ventricle
Trabeculae Carneae - series of ridges formed by raised bundles of cardiac muscle fibers
Papillary Muscles - chordae tendineae are connected to this - cone-shaped trabeculae carneae
Right Atrium
Superior and inferior vena cava and coronary sinus all dump here
Blood leaves the right atrium through the tricuspid valve and into the right ventricle
Superior and inferior vena cava and coronary sinus all dump here
Blood leaves the right atrium through the tricuspid valve and into the right ventricle
Right Ventricle
Right ventricle is separated from the left ventricle by a partition called the interventricular septum
Blood passes from the right ventricle through the pulmonary valve into the pulmonary trunk - divides into right and left pulmonary arteries
Right ventricle is separated from the left ventricle by a partition called the interventricular septum
Blood passes from the right ventricle through the pulmonary valve into the pulmonary trunk - divides into right and left pulmonary arteries
Left Atrium
Pulmonary vein brings deoxygenated blood to left atrium moves through bicuspid valve which has a more robust myocardium (because it pumps blood to the entire body)
Blood passes through the bicuspid valve (left AV valve)
Pulmonary vein brings deoxygenated blood to left atrium moves through bicuspid valve which has a more robust myocardium (because it pumps blood to the entire body)
Blood passes through the bicuspid valve (left AV valve)
Left Ventricle
thickest part of the heart
forms the apex of the heart
Blood passes from the left ventricle through the aortic valve into the ascending aorta - some of the blood in the aorta flows into the coronary arteries which branch from the ascending aorta...
thickest part of the heart
forms the apex of the heart
Blood passes from the left ventricle through the aortic valve into the ascending aorta - some of the blood in the aorta flows into the coronary arteries which branch from the ascending aorta and carry blood to the heart wall
remainder of the blood passes into the arch of the aorta and descending aorta
Flow of Blood
Right Atrium (deoxygenated blood) --> Tricuspid valve --> Right Ventricle --> Pulmonary Valve --> pulmonary trunk and pulmonary arteries --> in pulmonary capillaries, blood loses CO2 and gains O2 --> pulmonary veins (oxygenated blood) --> Left atrium --> Bicuspid valve --> Left ventricle --> Aortic valve --> Aorta and systemic arteries --> In systemic capillaries, blood loses O2 and gains CO2 --> Comes in through superior vena cava, inferior vena cava, and coronary sinus back to right atrium
Fibrous Skeleton of Heart
Heart valves located here
Anchor valves
Prevents over-stretching
Anchors cardiac muscle fibers
Electrical insulation between the atria and ventricles - finer scale coordination of the contraction of the atria vs. the ventricles - without this level of insulation, being able to properly coordinate the rate of heart contraction would be very difficult
Valve Coordination
Ventricular Diastole
Ventricular Systole
Ventricular Diastole
ventricles fill with blood (relaxation) - global relaxation of the heart followed by systole
Ventricular Systole
blood sent to pulmonary and systemic loops
Ventricles contract and the semilunar valves open and the AV valves close
Valve Disorders
Stenosis
Insufficiency
Rheumatic Fever
Stenosis
narrowing
problem when the aorta narrows - limits the amount of blood that can leave the heart and will increase the pressure of the blood as it leaves the heart
Insufficiency
valves won't completely close - get back-flow of blood
Aortic Insufficiency - blood comes back into the left ventricle
Mitral Insufficiency - blood is flowing from left ventricle into the left atrium
Mitral Valve Prolapse - the valve just completely back-flows blood - this is when people need to get valvular replacement
Rheumatic Fever
can lead to vegetative plaques on the valves and these nodules will keep the valves from closing
Coronary Circulation (Arteries)
Ascending aorta --> Coronary Arteries
    Left coronary Artery --> Anterior interventricular branch (services both ventricles) --> circumflex branch  (left atrium and ventricle)
    Right Coronary Arteries --> Atrial branches (small; right atriu...
Ascending aorta --> Coronary Arteries
Left coronary Artery --> Anterior interventricular branch (services both ventricles) --> circumflex branch (left atrium and ventricle)
Right Coronary Arteries --> Atrial branches (small; right atrium) --> Marginal branch (right ventricle) --> posterior interventricular branch (both ventricles)
Coronary arteries are terminal arteries, they don't necessarily have anastomoses (connections with other arteries for collateral circulation - alternate routes) though they can do so - anastomoses very susceptible to atherosclerosis
Coronary Circulation (Veins)
After blood passes through the arteries of coronary circulation, it passes into capillaries where it delivers oxygen and nutrients to the heart muscle and collects carbon dioxide and wastes - blood enters the veins
Left coronary artery --> ventri...
After blood passes through the arteries of coronary circulation, it passes into capillaries where it delivers oxygen and nutrients to the heart muscle and collects carbon dioxide and wastes - blood enters the veins
Left coronary artery --> ventricles and left atrium --> great cardiac vein --> posterior interventricular branch --> ventricles --> middle cardiac vein --> right atrium and ventricle --> small cardiac vein --> right ventricle --> anterior cardiac veins --> coronary sinus --> right atrium
Great Cardiac Vein
wraps around and comes to the coronary sinus
drains all of the heart with the exception of aspects of the right atrium and ventricle - for that we have two separate vessels
Drains the areas of the heart supplied by the left coronary artery (left and right ventricles and left atrium)
Small Cardiac Vein
wraps around and goes into coronary sinus, draining the right atrium and right ventricle
Anterior Cardiac Vein
generally there are several (can be up to 5)
help to drain the right ventricle and they loop over the coronary artery and dump directly into the right atrium (independently) - can spot them because they go over the right coronary artery
Myocardial Ischemia
reduced blood flow to the myocardium
Hypoxia - deficiency in the amount of O2 reaching the tissues
Angina Pectoris - chest pain
Mycardial Infarction (MI)
Death of an area of myocardium due to lack of blood flow
Heart attack
Fibrosis --> weakened heart
Ventricular Fibrillation
Cardiac Conduction System
1. Sinoatrial (SA) Node - natural pacemaker - atria contract
2. Atrioventricular (AV) Node - time for atria to empty blood into ventricles
3. Atrioventricular (AV) Bundle [Bundle of His] - only site where action potentials can conduct from the atria to the ventricles (elsewhere, the fibrous skeleton of the heart electrically insulates the atria from the ventricles)
4. Right and Left Bundle Branches
5. Purkinje Fibers - ventricular contraction - moves upward from the apex, and blood is pushed toward the semilunar valves
Cardiac Conduction System Part 2
SA node --> 90-100 action potentials/min (bpm)
Vagus nerve --> acetylcholine --> 75 bpm
Electrocardiogram (ECG or EKG) composite of all 'electrical' activity (action potentials) generated by nodal and contractile cells
Membrane potentials
Resting membrane potential
Depolarization vs. repolarization
Depolarization: reduction in the membrane potential; the inside of the membrane becomes less negative than the resting membrane potential
Repolarization: restoration of the resting membrane potential
Normal EKG: A Single Heartbeat
P Wave: SA node depolarization
QRS Complex: ventricular depolarization
T Wave: ventricular repolarization
P Wave: SA node depolarization
QRS Complex: ventricular depolarization
T Wave: ventricular repolarization
Heart Rhythm
Normal sinus rhythm - usual rhythm of heartbeats, established by the SA node
Arrhythmia (dysrhythmia) - abnormal rhythm as a result of a defect in the conduction system of the heart
Bradycardia < 50 bpm
Tachycardia > 100 bpm
Extrinsic Control of the Heart
Cardiac plexus - forms synaptic junctions with the nodal tissues and the coronary vessels - autonomic nervous system - two parts:
Cardiac branches of Vagus (X) nerve
Cardiac branches of cervical and upper thoracic sympathetic trunk nn. (T1-4)
Sympathetic Response: heart rate speeds and coronary arteries dilate
Parasympathetic Response: heart rate slows and coronary arteries constrict
Artificial Pacemakers
SA (100 bpm)
AV (40-60 bpm)
AV bundle, etc. (20-35 bpm)

Battery + impulse generator, connected to two leads
Cardiac Cycle
Relaxation: all chambers in diastole
- Most of ventricular filling (75%) occurs
Pressure of the atria versus pressure of the ventricles versus pressure of vasculature
Atrial Systole
- AV open, SL closed
Ventricular Systole
- AV closed, SL closed --> open
Heart Sounds
S1 (lubb) - blood turbulence as AVs close
S2 (dupp) - blood turbulence as SLs close
S3 - blood turbulence during ventricular filling
S4 - blood turbulence during atrial systole
Heart Murmur
abnormal sounds
- Clicking, gurgling, rushing
- Typically benign in children
- Valve disorder in adults
Exercise and the Heart
Aerobic Exercise (3-5x weekly)
Cardiac output (stroke volume)
Cooperation with respiratory system
Angiogenesis - development of new blood vessels from pre-existing ones
Physiological vs. Pathological Cardiomegaly
- enlargement of the heart
- Physiological - athletes get this - muscle enlarged from working out
- Pathological - sickness - hypertrophy of heart
Coronary Artery Disease (CAD)
Atherosclerotic plaque --> mycardial ischemia
Risk Factors: smoking, arterial hypertension, diabetes mellitus, obesity, hyperlipoproteinemia, age, being male, etc.
Lipoproteins
Low-density (LDLs): liver --> cells; "bad cholesterol"
High-density (HDLs: cells --> liver; "good cholesterol"
Inflammation
Fatty streak = foam cells, macrophages, and T cells
CAD Diagnosis
EKG
Stress test
Radionuclide Imaging
Echocardiography
Electron Beam Computerized Tomography (EBCT)
Coronary Computer Tomography Radiography (CCTA)
Cardiac Catheterization
Coronary Angiography
CAD Treatment
Coronary artery bypass grafting (CABG) "cabbage" - blood vessel from another part of the body is attached to a coronary artery
Percutaneous transluminal coronary angioplasty (PTCA), and stenting
Blood Vessels
Arteries - away from the heart
Arterioles - resistant vessels
Capillaries - permeable, exchange
Venules
Veins - towards the heart
Angiogenesis - formation of new blood vasculature
Angiogenesis and Disease
Tumor Angiogenesis Factors (TAFs) - secreted from tumors that stimulate blood vessel growth to provide nourishment for the tumor cells
Vascular Epithelial Growth Factor (VEGF)
Basic Fibroblast Growth Factor (bFGF)
Proliferative Diabetic Retinopathy - angiogenesis may be important in the development of blood vessels that actually cause blindness, so finding inhibitors of angiogenesis may also prevent the blindness associated with diabetes
Blood Vessel Structure
Tunica Interna (intima)
Tunica Media
Tunica Externa

Arteries have elastic lamina present while in veins they are absent
Arteries have very well defined tunica media whereas veins do not
Veins have valve flaps that allow one way flow of blood
Tunica Interna (intima)
Tunica Media
Tunica Externa

Arteries have elastic lamina present while in veins they are absent
Arteries have very well defined tunica media whereas veins do not
Veins have valve flaps that allow one way flow of blood
Tunica Interna
endothelium (thin layer of flattened cells) + basement membrane (provides a physical support base for epithelial layer)
internal elastic lamina - forms the boundary between the tunica interna and tunica media - facilitate diffusion of material through the tunica interna to the thicker tunica media
Tunica Media
smooth muscle
Vasoconstriction vs. vasodialation
external elastic lamina - forms the outer part of the tunica media and separates the tunica media from the outer tunica externa
Tunica Externa
Elastic and collagenous fibers
Contains lots of nerves
Vasa vasorum - small vessels that supply blood to the tissues of the vessel
Helps anchor the vessels to surrounding tissues
Transverse Section of Artery
Arteries (Efferent)
Elastic (conducting) Arteries
Muscular (distributing) Arteries
Anastomoses
Elastic (Conducting) Arteries
Largest (ex. aorta, pulmonary trunk)
Walls about 10% of vessel diameter
Well-defined elastic laminae
Thick tunica media (elastic lamellae)
Function as pressure reservoirs - as blood pumps into them they expand and then they snap putting more force on the blood to move forward
Feed into muscular arteries
Muscular (Distributing) Arteries
Thick, muscular tunica media (3 --> 40+ layers) - can really regulate the blood by vasodilation or vasoconstriction
Walls about 25% vessel diameter
Vascular tone - the greater the tone the greater the resistance on the blood
Ex. right and left arteries
Arterioles
Resistance vessels (autonomic control = sympathetic)
Thin tunica interna and thin internal elastic laminae
Walls about 50% of vessel diameter
Feed into capillary beds

Microcirculation
Metarteriole (terminal end of the arteriole) --> thoroughfare channel --> Pre-capillary sphincters (allows or restricts blood into capillary bed) --> capillaries --> venule
Capillaries
Exchange vessels (blood <--> interstitial fluid)
Lack tunica media and tunica externa
Diameter about 5-10 um
Distribution dependent upon metabolic need
Capillary Types
Continuous
Fenestrated
Sinusoid
Continuous Capillary
CNS, skin, lungs, skeletal, and smooth muscle, and connective tissues
Fenestrated Capillary
kidneys, small intestinal villi, choroid, plexuses, ciliary processes (eyes), most endocrine glands
Has spaces
Sinusoid Capillary
Liver, red bone marrow, spleen, adenohypophysis, parathyroid and adrenal glands
Areas where exchange in capillary beds is frequent and very important where these capillaries are
Venules --> Veins
Afferent
Postcapillary venules --> muscular venules --> veins
Thin tunica media and tunica interna
Thick tunica externa
Walls about 10% of diameter
Low blood pressure --> Valvular
Muscle milking - when you place a major vein between or next to skeletal muscles - as these muscles contract and relax they do the same to the veins
Respiratory milking
Venous Valves
thin folds of tunica interna that form flap-like cusps
low blood pressure in veins allows the flow of blood returning to the heart to slow and even back up; aid in venous return by preventing backflow
Varices
Singular - Varix
These valves can sometimes fail and when they fail blood can back up (pool) in veins and they can be stretched 
Varicose veins - treatable 
Not muscularized and gravity as it pulls blood back down it closes the valve (in a normal vein) - if this...
These valves can sometimes fail and when they fail blood can back up (pool) in veins and they can be stretched
Varicose veins - treatable
Not muscularized and gravity as it pulls blood back down it closes the valve (in a normal vein) - if this doesn't happen it causes varices
Venous Thromboembolism (VTE)
Deep vein thrombosis (DVT) followed by pulmonary embolism (PE) - makes itself up through the limbs and goes up the lungs and occludes blood flow there
Vena Comatins - if you bundle vein with artery then the action of the pulsing artery will help move blood forward
Blood Pressure
Diminished blood pressure which is why you need to push it up as you get to the venules and veins
Diminished blood pressure which is why you need to push it up as you get to the venules and veins
Portal Systems
Portal vessels (veins) connecting capillary beds
Hepatic - blood is being taken to the liver
Hypophyseal - blood is being taken to the neurohypothesis of the pituitary gland from the hypothalamus
Renal - blood is being moved around the nephron (humans do not have this)
Blood Distribution
At rest:
64% systemic veins and venules
13% systemic arteries
7% systemic capillaries
9% pulmonary vasculature
7% heart
Systemic veins as blood reservoirs
Venoconstriction- forces blood back to the arteries
Circulatory Routes
Systemic
Coronary
Cerebral
Hepatic portal
Nutrient arteries to lungs
Pulmonary
Fetal
Aorta Circulation
Ascending aorta (aortic valve)
Aortic arch - descends and ends at C4-C5
Thoracic Aorta - passes through diaphragm to become..
Abdominal Aorta - divides into common iliac arteries
Ascending Aorta Branches
Right and left coronary arteries
Arch gives rise to all vasculature that serves the upper limbs and neck
Right and left coronary arteries
Arch gives rise to all vasculature that serves the upper limbs and neck
Aortic Arch Branches
Three major branches:
    Brachiocephalic Trunk- right common carotid artery and right subclavian artery
    Left Common Carotid Artery
    Left Subclavian Artery

Subclavian supply the upper limbs
Common Carotid largely supplies head and neck
Three major branches:
Brachiocephalic Trunk- right common carotid artery and right subclavian artery
Left Common Carotid Artery
Left Subclavian Artery

Subclavian supply the upper limbs
Common Carotid largely supplies head and neck
Common Carotid Artery Branches
Carotid sinus - where you feel your pulse - divide into external and internal carotid arteries
Internal carotid arteries go inside your skull and branch (largely for your branch) and external carotid arteries will branch outside of your skull and...
Carotid sinus - where you feel your pulse - divide into external and internal carotid arteries
Internal carotid arteries go inside your skull and branch (largely for your branch) and external carotid arteries will branch outside of your skull and supply your head and face and superficial skull
Subclavian Artery Branches
Subclavian turns into:
Axillary --> Bracial --> Radial and Ulnar Arteries
Subclavian turns into:
Axillary --> Bracial --> Radial and Ulnar Arteries
Thoracic Aorta Branches
Two branches:
   Visceral: Pericardial, Bronchial, Esophageal, Mediastinal branches
   Parietal: Posterior Intercostal, Subcostal, Superior phrenic
Two branches:
Visceral: Pericardial, Bronchial, Esophageal, Mediastinal branches
Parietal: Posterior Intercostal, Subcostal, Superior phrenic
Abdominal Aorta Branches
After we cross the diaphragm we are now in the abdominal aorta
Pay most attention to what is numbered as visceral branches
  Major branch: celiac trunk
  Major branch: superior mesenteric - picks up where the celiac left off - remainder of duod...
After we cross the diaphragm we are now in the abdominal aorta
Pay most attention to what is numbered as visceral branches
Major branch: celiac trunk
Major branch: superior mesenteric - picks up where the celiac left off - remainder of duodenum, all of small intestines, and the first 2/3's of the large intestine - division where the superior mesenteric stops and inferior mesenteric picks up is part of the colon (sphrenic flexor)
Major branch: from the sphrenic flexur through the sigmoid colon through the rectum is supplied by the inferior mesenteric
Series of arteries between superior and inferior mesenteric - suprarenal (sit on top of kidneys) kidneys are fed by renal arteries directly and the gonadal arteries will services the gonads
Pancreas serviced by celiac and inferior mesenteric - inferior mesenteric from below and celiac provides vasculature to superior portion
Abdominal Aorta Branches and Legs
Splits to common iliac arteries (right and left) 
Splits again into external and internal iliac arteries
External artery also known as femoral artery which will eventual turn in popliteal artery and then tibial (posterior and anterior) and fibul...
Splits to common iliac arteries (right and left)
Splits again into external and internal iliac arteries
External artery also known as femoral artery which will eventual turn in popliteal artery and then tibial (posterior and anterior) and fibular artery

Common iliac aa --> external iliac aa. --> femoral aa. ******
Major Systemic Veins
Superior Vena Cava: head, neck, thorax, and upper extremities
Inferior Vena Cava: abdomen, pelvis, and lower extremities
Coronary Sinus: heart
Brachiocephalic Veins: supplied by a subclavian vein and an internal jugular
All major veins drain in to the right atrium
Thoracic Veins
Venipuncture
Cubital vein - crosses the cubital fossa - connected the cephalic and basilic vein - major veins of the upper limb are superficial veins - first place to go for blood draw
In the lower limbs, the major veins are deep whereas the minor veins are s...
Cubital vein - crosses the cubital fossa - connected the cephalic and basilic vein - major veins of the upper limb are superficial veins - first place to go for blood draw
In the lower limbs, the major veins are deep whereas the minor veins are superficial***
Great Saphenous Vein
Starts at the medial miolis - dumps into the femoral vein
Clinically important for two reasons:
1. If doctors need a graft they will go to great saphenous vein (it is superficial and large) [CABG]
2. important region for doing saphenous vein cut down - when a surgeon visualizes a superficial vein and opens the skin around it so you have direct access to the vasculature - if you have to put in a line and rehydrate immediately want to do this here
Hepatic Portal Circulation
delivers blood to the liver
Superior mesenteric and splenic veins unite to form this - after passing through the liver, blood drains into the hepatic veins, which then empty into the inferior vena cava
Includes, celiac, superior mesenteric and inferior mesenteric
At the same time the liver is receiving nutrient-rich but deoxygenated blood via the hepatic portal vein, it also is receiving oxygenated blood through the hepatic artery, a branch of the celiac trunk
Pulmonary Circulation
Carries deoxygenated blood from the right ventricle to the air sacs within the lungs and returns oxygenated blood to the left atrium
Pulmonary trunk from the right ventricle --> divides into right and left pulmonary artery (only arteries that carry deoxygenated blood) --> air exchange in capillaries --> pulmonary veins which exit the lungs and carry oxygenated blood to the left atrium (two left and two right pulmonary veins enter the left atrium)
Fetal Circulation
Umbilical arteries (2): fetus --> placenta
Umbilical Vein: placenta --> fetus
Ductus venosus: umbilical vein --> inferior vena cava
- Birth --> ligamentum venosum (ductus venosus)
- Birth --> ligamentum teres heparis (umbilical vein)
Ductus arteriosus: pulmonary trunk --> aorta
- Birth --> ligamentum arteriosum
Foramen Ovale: blood passes through right atrium --> left atrium
- Birth --> fossa ovalis
Blood Vessel Development
Mesoderm --> mesenchyme --> hemangioblasts (both blood vessels and blood cells develop from this)
Angioblasts (form blood vessels)--> blood islands
Space coalesce to form lumen
Hypertension
Primary - persistent, idiopathic
Secondary - identifiable cause
Lifestyle decisions:
- Weight, exercise, alcohol consumption, salt consumption, smoking, stress
Lymphatic System
lymph, lymph vessels, lymphatic organs, and red bone marrow
Reticular connective tissue + lymphocytes
Functions:
- Drains excess interstitial tissue
- Transports lipids and lipid soluble vitamins (A, D, E, and K)
- Immune responses
Lymphocytes
B cells --> plasma cells (produce antibodies) --> memory B cells (can mount an even stronger immune response if the same antigen attacks the body)
T cells:
- T-helper cells - work with B cells to amplify antibody production by plasma cells
- T cytotoxic cells (destroy target cells) --> T memory cells ("remember" an antigen and mount a more vigorous response if the same antigen attacks the body)
- T regulatory cells - can turn off immune response by supressing T cells - important for autoimmune diseases
Lymph Circulation
Lymphatic capillaries -->
- Very permeable
- Unidirectional flow
- Lacteal and chyle (small intestine)
Lymph vessels -->
- Lymph nodes
- Skin: follow veins
- Viscera: follow arteries
Lymph trunks
- Lumbar trunks: lower limbs, pelvis, kidneys, etc.
- Intestinal trunks: stomach, intestines, liver, pancreas, and spleen
- Bronchomediastinal trunks: thorax, lungs, and heart
- Subclavian trunks: upper limbs
- Jugular trunks: head and neck
Thoracic (left lymphatic) Duct and Right Lymphatic Duct
- Cisterna chyle (receives lymph from the right and left lumbar trunks and from the intestinal trunk) --> Thoracic duct (main duct for return of lymph to blood)
Edema
Swelling
Filtration >> Reabsorption - water retention
about 30% threshold
Lymph Flow
Aided by "pumps"
- Skeletal Muscle - aided by skeletal muscle contracting and relaxing
- Respiratory - arteries pulsing will help move fluid
Deeper lymphatic muscles have closer connections with arteries because the pulsing will help move lymphatic fluid through the system
Lymphatic Organs and Tissues
Primary lymphatic organs
Secondary lymphatic organes and tissues
Primary Lymphatic Organs
sites where stem cells divide and become immunocompetent (lymphocytes get exposure to antigen and are becoming active for that specific antigen)
- Thymus
- Red bone marrow
Secondary Lymphatic Organs and Tissues
sites where most immune responses occur
- Thymus
- Lymph nodes and nodules (difference is a capsule - node has a capsule nodule does not)
- Spleen - has a capsule
Thymus
bilobed, capsulated (each lobe capsulated)
located in the mediastinum
Cortex: T cell selection and maturation - t-cells are being activated against specific antigens but also learning to recognize self from non-self
- 2% survive - because of the difficulty recognizing non-self - go to the medulla
Medulla:
- Thymic corpuscles - serve as sites of T cell death in the medulla
Atrophies with age - after puberty thymus gland is shrinking
Lymph Nodes
Bean-shaped and typically clustered
Capsule and compartments - capsulated
Outer Cortex
- Lymphatic nodules - full of B cells
Inner Cortex
- T cells and dendritic cells
Medulla
- B cells, plasma cells and macrophages
Afferent vessels --> sinus --> efferent vessels (hilus)
Inguinal Lymph Node
By femoral artery and vein
Drain the lymphatic vessels of the lower limbs
Metastasis
Spread of a disease (or tumor)
typically via vasculature
Follow lymph vessels
"Firm and fixed" - become anchored to a location and are very firm
- Lymphaginous - moves through lymphatic system
- Hematoginous - moves through the circulation
- Atagenic - messed up by doctor
Spleen
Left hypochondriac region - right under the diaphragm - superior to left kidney and splenic flexor
Largest single mass of lymphatic tissue - encapsulated organ
Serves a dual function - two types of pulp - white and red
- White pulp: lymphocyte action
- Red pulp: macrophages digesting old RBC's, platelet storage, hemopoiesis (in fetus)
Blood enters through splenic artery
Lymphatic Nodules
Acapsular
AKA mucosa associated lymphatic tissue (MALT)
- Tonsils - five tonsils (two paired, one unpaired)
- Pharyngeal (adenoid) - anterior posterior aspect of nasal pharynx - not paired
- Palatine - tonsilar fossa
- Lingual - base of tongue
- Lamina propria (connective tissues) of mucous membranes
- Aggregated lymphatic follicles (Peyer's patches) - located in the ileum of the small intestine
Tonsillitis
Typically viral, but can also be group A streptococcal infection
Time, antibiotics
Tonsillectomy
Sometimes tonsil tissue will re-grow
Signs of Infection
Lymphadenopathy - enlarged, tender
- Generalized or localized
Lymphadenitis - skin over the lymph node becomes inflamed as a result of lymphadenopathy
Bad when lymph node becomes large and becomes fixed and it's not painful
Respiratory System
Coordinates with cardiovascular system
O2 in for chemoiosmosis
CO2 waste expelled
CO2 = volatile acid
Nasal and oral cavities <--> pharynx <--> larynx <--> trachea <--> bronchi ,--> alveoli
Can adjust the pH of our blood by adjusting our breathing
Anatomy of Respiratory System
Upper: nose --> pharynx
Lower: larynx --> lungs
Conducting Zone: filter, warm, and moisten air and conduct it into the lungs
Respiratory Zone: main sites of gas exchange between air and blood
External Nose
Primary route of inhalation
External Nares - openings into the external nose (nostrils)
External nares --> nasal vestibule --> internal nares
Primary route of inhalation
External Nares - openings into the external nose (nostrils)
External nares --> nasal vestibule --> internal nares
Internal Nose and Nasopharynx
Respiratory vs. olfactory epithelium
Warms, filters, moistens incoming air
Lining the lateral walls are the conchae - own independent bones - middle and superior conchae are elaborations of the ethmoid bone
Olfaction
Modifications of speech vi...
Respiratory vs. olfactory epithelium
Warms, filters, moistens incoming air
Lining the lateral walls are the conchae - own independent bones - middle and superior conchae are elaborations of the ethmoid bone
Olfaction
Modifications of speech vibrations
Nasopharynx - division of pharynx
Opening of the auditory tube - goes to the middle ear
As we cross the plane, move to the oropharynx
Nasal Conchae
Superior
Middle
Inferior
Oropharynx and Laryngopharynx
Shared space for consumption and respiration
Gloosopharyngeal (IX) and Vagus (X) nerve
Hypopharynx (at the hyoid)
Epiglottis - part of the laryngopharynx
Shared space for consumption and respiration
Gloosopharyngeal (IX) and Vagus (X) nerve
Hypopharynx (at the hyoid)
Epiglottis - part of the laryngopharynx
Coryza, Influenza, Etc.
Coryza - common cold symptoms
- Viral
- Sneezing, rhinorrhea, cough, and congestion
Seasonal Influenza
- Fever, chills, muscle aches
- Seasonal flu vaccine modified to what epidemiologists thinks will be bad
H1N1 Influenza
- Deadly
Larynz
Connects the laryngopharynx to the trachea
"Voice box"
C4-C6
9 Cartilages: 3 paired, 3 unpaired
- Epiglottis
- Thyroid (Adam's Apple)
- Cricoid
- Arytenoid (2)
- Corniculate (2)
- Cuneiform (2)
Important Features of Larynx
Thyroid cartilage - largest and most robust
Epiglottis - one cartilage that rises above at rest - attached to anterior rim of the thyroid cartilage
Cricoid Cartilage - forms complete cartilogenous ring around the larynx - base upon which the cor...
Thyroid cartilage - largest and most robust
Epiglottis - one cartilage that rises above at rest - attached to anterior rim of the thyroid cartilage
Cricoid Cartilage - forms complete cartilogenous ring around the larynx - base upon which the corniculate will sit***
Trachea - has a series of hyaline cartilage rings that are incomplete
Arytenoid Cartilage - attack to the vocal folds (true vocal cords) - creat sound
Ventricular folds - false vocal cords - first things you can see
Rima Glottidis - space between the vocal cords - space through which you are breathing
Vocal chords are typically abducted
Laryngitis and Laryngeal Cancer
Laryngitis - inflammation of the larynx
- Respiratory infection
- Irritants
Laryngeal Cancer
- Cigarette smoking - when you smoke, increase risk of cancer 10x - when you drink, increase risk of cancer by 4x - smoke and drink increase risk of cancer by 40x - multiplicative effects
- Radiation therapy and/or surgery
Voice Production
vocal folds vibrate --> voice production
- Controlled by ten intrinsic laryngeal muscles
- More tension = higher pitch
- Greater air pressure = louder sound
Nearly closed vocal folds --> whisper (vocal cords are adducted)
Valsalva maneuver and the ventricular folds
- Do it when you defecate - adduct your vocal chords and putting pressure on your abdominal pelvic cavity - helps you go to the bathroom
Vocal Folds Abduction
Can pivot - swing medially or laterally
When they swing laterally, they abduct - rima glottidis gets bigger
Posterior cricoarytenoid muscle - pivots so they can swing around and abduct - necessary for breathing and producing voice
Lateral crico...
Can pivot - swing medially or laterally
When they swing laterally, they abduct - rima glottidis gets bigger
Posterior cricoarytenoid muscle - pivots so they can swing around and abduct - necessary for breathing and producing voice
Lateral cricoarytenoid muscle - adduct vocal chords (pulls them together)
Trachea
tubular connection from larynx --> bronchi
About 12 cm length and 2.5 cm diameter
Layered:
- Mucosa - pdeudostratified ciliated columnar ET
- Submucosa - areolar CT and seromucous glands
- Media - C-shaped hyaline cartilage rings - most prominent feature
- plus fibromuscular membrane (embedded trachealis muscle) - smooth muscle - contract when you forcefully exhale something - brings end of the C close together and constricts the trachea
- Adventitia - areolar CT
Tracheotomy and Intubation
Tracheotomy/Tracheostomy - longitudinal incision inferior to the cricoid cartilage
Cricothyrotomy - incision between thyroid and cricoid cartilage (emergency airway only)
Intubation - tube passed through nose or mouth through the larynx in to trachea
Bronchial Tree
Trachea --> Primary bronchi (right and left) --> Secondary (lobar) bronchi (right =3, left = 2) --> tertiary (segmental bronchi) --> bronchioles --> terminal bronchioles
- Terminus of the conducting zone
- Clara cells (= club cells)
- Protective, produce surfactant, reserve (stem) cells
Bronchial Tree - Important Features
End of trachea - splits into two primary bronchi (serve right and left lungs respectively)
Ridge called the carina - separates air as it moves in - very vascularized - if something hits it you will into spasmatic coughing
Right side is more robu...
End of trachea - splits into two primary bronchi (serve right and left lungs respectively)
Ridge called the carina - separates air as it moves in - very vascularized - if something hits it you will into spasmatic coughing
Right side is more robust than the left
From the primary bronchi separate into secondary bronchi where you can branch into different lobes of the lung - secondary bronchi divide into tertiary bronchi
Tertiary bronchi serve as bronchopulmonary segment - serviced by tertiary bronchis and has it's own blood supply - it is surgically receptible without compromising the rest of the lung***
Broncioles --> Terminal bronchioles --> respiratory bronchioles
Bronchial Histology and Physiology
Trends as the branching in the bronchial tree becomes more extensive:
- Reduction of cilia and goblet cells
- Reduction in cartilages
- Increase in smooth muscle
Sympathetic --> epinephrine and norepinephrine release --> airway dilation
Bronchial arteries and veins (NB pulmonary veins)
- Bronchial arteries will branch off of descending aorta - what is odd is that returning of the blood to the heart - very little of blood returns via bronchial veins - some people's don't have any at all - about 90% of the blood gets dumped into the pulmonary veins - odd because its deoxygenated blood headed back to the left atrium which will mix with highly oxygenated blood - strange****
Asthma
Spasm of the bronchiolar smooth muscle
- Bronchoconstriction
- Allergens, anxiety, irritants
Steroids that help alleviate some of the issues in respect to allergens and irritants and bronchodilators that help with symptoms
Chronic Bronchitis
Excessive bronchial mucous secretion and cough
Excessive amount of mucous produced - makes it difficult to move air in and out of the lungs and may go to the lungs which is very irritating
Mucous elevator impairment
Lungs
Pleural membrane
  - Parietal Pleura - lines thoracic - on the body wall
  - Visceral Pleura - directly adherent to the lung - covers lung
  - Pleural cavity - space between the parietal and visceral pleura
Fissures - separate lobes of the lun...
Pleural membrane
- Parietal Pleura - lines thoracic - on the body wall
- Visceral Pleura - directly adherent to the lung - covers lung
- Pleural cavity - space between the parietal and visceral pleura
Fissures - separate lobes of the lung
- Separating the middle lobe from the superior lobe is the horizontal fissure - separating the inferior from everything else is the oblique fissure
Hilum - roots of the lung - includes pulmonary arteries, pulmonary veins, and depending on where you make this cut (if it's right at the lungs you'll have a right and left primary bronchi)
Impression on the lung - room for the spinal cord and trachea and aortic arch - most conspicuous space is for the heart
Cardiac Notch - for the heart - asymmetry in the lungs because of the position of the heart - the lungs are domed to accommodate the diaphragm
Bronchopulmonary Segments
has it's own unique segmental bronchi and vasculature meaning they are independent units of each other
An individual bronchial segment can be removed individually without affecting the other bronchial segments
**Learn two things from this: if yo...
has it's own unique segmental bronchi and vasculature meaning they are independent units of each other
An individual bronchial segment can be removed individually without affecting the other bronchial segments
**Learn two things from this: if you aspirate something 9/10, it will go to the right - if something is small enough to get into a bronchopulmonary segment it will usually end up in the superior segment of the inferior lobe - fluid will drain into the superior segment of the inferior lobe as well if someone is sitting in bed for a long time with some sort of lung infection
Lobules of Lung
Encapsulate within a bronchopulmonary segment a respiratory region of the respiratory zone
Terminal Bronchiole - part of the conducting zone and branches into respiratory bronchioles which have alveolar ducts that lead to alveolar sacs which are surrounded by capillary beds which connect pulmonary arteries and veins - purpose it to maximize surface area so you can have a larger respiratory surface to exchange gas
Terminal bronchioles --> respiratory bronchioles (start of respiratory zone) --> alveolar ducts --> alveolar sacs --> alveoli
Smoking and the Respiratory System
Nicotine restricts terminal bronchioles
CO binds to hemoglobin - causes hypoxia
Increased bronchial mucous production (by goblet cells) and mucosal edema
Converts respiratory epithelium to squamous epithelium
Destroys elastic fibers of lungs
An individual can completely lose their mucous elevator
Ultimately will have COPD - starts with emphysema
Alveoli
Two types of cells that comprise the walls:
- Type I Alveolar Cells - diffusion membrane for gases
- Type II Alveolar Cells - septal cells - secrete alveolar fluid to help lower the surface tension
Alveolar macrophage - keeps an accumulation of foreign cells in lung by phagocytizing the material
Respiratory Membrane
.5 um thick
Layered (epi-/endothelial sandwich)
- Alveolar wall (type I and type II alveolar cells)
- Epithelial basement membrane
- Capillary basement membrane
- Endothelium of capillary
70m2 = size of a handball court
Emphysema
Alveolar wall destruction
Loss of surface area for respiration
Destruction of elastic capacity of lungs --> COPD
Lowered blood O2 saturation
May be a precursor to lung cancer
Barrel chested
Mucous elevator is gone and are potentially suffering chronic bronchitis
Lung Cancer
Leading cause of cancer deaths in the U.S.
85% smoking related (risk factor 10-30x greater)
Bronchiogenic carcinoma
- Adenocarcinoma: glandular ET (most common)
- Squamous cell carcinoma: larger bronchial tube ET
- Small Cell Carcinoma: primary bronchi ET
Respiration
Pulmonary Ventilation: atmosphere <--> lungs
External (Pulmonary) Respiration: lungs <--> blood
Internal (Tissue) Respiration: blood <--> interstitial fluid and cells
Cellular Respiration: manufacturing ATP
Pulmonary Ventilation (breathing)
Pressure - driven (1 atm = 760 mmHg)
Boyle's Law: PV = k
Inhalation: P thoracic cavity < P atmosphere
Exhalation: P thoracic cavity > P atmosphere
Primary Muscles: diaphragm and intercostal muscles
Accessory Muscles: abdominals, SCM, and scalene muscles
Alter pressure by altering the volume
Muscular Control of breathing
Diaphragm - most important for respiration - sets the boundary between the abdominal and thoracic cavity - moves inferiorly which increases the volume of the thoracic cavity therefore decreasing pressure
Generally tidal volume during quiet breath...
Diaphragm - most important for respiration - sets the boundary between the abdominal and thoracic cavity - moves inferiorly which increases the volume of the thoracic cavity therefore decreasing pressure
Generally tidal volume during quiet breathing is 500 mL
Accessory muscles for inhalation (increase the volume of the diaphragm) - sternocleidomastoid and posterior, middle, and anterior scalenes (attach to ribs and yank them upwards) - external intercostal grab the ribs and pull them up and out
Muscles of exhalation - internal intercostals pull ribs inwards and down - abdominals are also important for exhalation because they have to do with the abdominopelvic cavity, force increases pressure and displaces diaphragm which decreases volume and pushes air out of the lungs
Respiratory Center of the Brain
Medullary Rhythmicity Center
Apneustic Area
Pneumotaxic Area
Medullary Rhythmicity Center
Apneustic Area
Pneumotaxic Area
Medullary Rhythmicity Center
Inspiratory area (2-3 sec): diaphragm (phrenic nn.) and external intercostal muscles (intercostal nn.) - when it is not stimulated the diaphragm relaxes
expiratory area: activates only during forceful breathing: internal intercostal muscles and abdominal muscles
Apneustic Area
stimulates the inspiratory area
Prolongs inhalation
Generally will slow respiration
Mnemonic: ASIA - apneustic stimulates the inspiratory area
Pneumotaxic Area
Inhibits the inspiratory area and shortens inhalation
Overrides the apneustic area
Regulation of Respiratory Center
Cerebral Cortex (cortical)
- voluntary changes
- Limited by [CO2] and [H+]
Hypothalamus and Limbic
- Emotional breathing (crying, laughing, etc.)
Chemoreceptors
- Central chemoreceptors (medulla): changes in CSF [CO2] and [H+]
- Peripheral Chemoreceptors: aortic and carotid bodies - changes in blood [O2], [CO2], [H+]
Bear Receptors - respond to being stretched
Can alter your levels of cardiac rate by massaging carotid sinus - shouldn't do this - activates the bear receptors and glossopharyngeal will slow down the heart rate because the bear receptors will say that the pressure is high
Inflation (Hering-Breuer) Reflex
Mediated by baroreceptors in bronchi/bronchioles
- Stretched (over-inflation) --> Vagus (X) stimulation --> inhibition of inspiratory and apneustic areas
Likely a protective mechanism
Exercise and Respiration
Pulmonary perfusion tied to cardiac output
Increases rate of oxygen diffusion
Changes in depth of respiration (moderate)
Changes in rate of respiration (strenuous)
Pneumonia
Acute infection of alveoli
Immune responses --> ventilation impairment
Commonly steptococcus pneumoniae
Development of Respiratory System
4 weeks: respiratory diverticulum (outgrowth of foregut) aka lung bud
- Endoderm --> epithelium and glands
- Splanchnic mesoderm --> CT and smooth muscles
Proximal RD --> tracheal bud --> bronchial buds
Weeks 6-16: all conductive elements form
Weeks 16-26: most respiratory elements form
Weeks 26+: maturation
Respiratory Distress Syndrome
Infants born 26-28 weeks severely at risk
Alveoli collapse during exhalation
Forced ventilation
Surfactant (lowers surface tension) - don't have enough of it
Aging and the Respiratory System
Loss of elasticity
Decrease in dust cell activity
Decrease in ciliary action
More prone to pulmonary infections
Urinary Trivia
Kidneys receive about 25% of cardiac output at rest
Number of nephrons set at birth
Kidney dysfunction may only be detectable at 25% of normal function
Renalectomy may cause hypertrophy of remaining kidney
- May increase to 80% function of both kidneys
Anatomy of Urinary System
Bilaterally paired kidneys - right sits a little lower than the left (liver causes this by depressing the kidney down)
Attached to the kidney at the hila are vasculature
Ureter - transport urine from the kidneys to the urinary bladder
Suprarena...
Bilaterally paired kidneys - right sits a little lower than the left (liver causes this by depressing the kidney down)
Attached to the kidney at the hila are vasculature
Ureter - transport urine from the kidneys to the urinary bladder
Suprarenal gland (sympathetic) - located superior to the kidneys
Renal Functions
Maintenance of extracellular volume and osmolarity
- [ions] Na+, K+, Ca2+, Cl-, and HPO4 2-
- pH: secretes H+, conserves HCO3-
- volume: H2O
- [glucose] glutamine --> gluconeogenesis or excrete
Endocrine: excrete 3 major hormones
- calcitriol: increase Ca2+ (PCT)
- Erythropoietin: erthrocyte production (peritub.)
- Renin: increase BP (juxtaglomerular apparatus)
Excretion: catabolic wastes, bioactive substances - excrete glucose if you have diabetes
Renin, Kidneys, and Liver
Kidney --> Renin
Liver: Angioteninsogen (when it has renin) --> turns into angiotensin I (with ACE you'll get) --> Angiotensin II which acts on the suprarenals to produce aldosterone
Lungs: ACE --> leads to production of angiotensin II
ACE Inhibitor: used for hypertension - blocks pathway so you don't get as much angiotensin II or aldosterone - look out for large drops in blood pressure
Retroperitoneal
Sprarenal glands
Aorta and IVC
Deodenum (proximal segment)
Pancreas (tail)
Ureters
Colon (ascending and descending)
Kidneys
Esophagus (thoracic)
Rectum (prox. 2/3)

Secondarily RP: Duodenum, pancreas, colon
Peritenium
Kidneys are behind the peritenium
Certain organs are retroperitenium - duodenum, ureter, kidney, bladder
Simple squamous epithelium with basement membrane - need to peel away to get to the kidney
Renal Fascia
Connective tissue that surrounds the kidney
Perirenal Fat
can be all around the neurovasculature
Fat and fascia important for anchoring the kidneys in place so they don't move too much
Kidneys move a little bit with respiration as the diaphragm displaces, they go down and then will go back up
Renal Cortex and Renal Medulla
Medulla is organized into renal pyramids
Cortex is all of the tissue that surrounds the medulla
Renal Column - much of the nephron is embedded in the cortex and the Loop of Henle goes into the medulla - extend between renal pyramids
Papilla - where the urine drops into the calyces - once urine makes it to the renal papilla cannot be reabsorbed
Papilla --> Minor Calyces --> Major Calyces --> Renal pelvis --> Ureter --> Urinary bladder
Nephroptosis
"Floating kidney"
Weakened fibrous attachments or sudden loss of adipose CT
--> hydronephrosis (death of nephron)
Nephroplexy for some symptomatic cases
Great risk because the ureters can kind and urine can't flow through so pressure builds up and the kidney can expand due to that pressure which can lead to damage to the kidney
Renal Circulation
Receive 20-25% cardiac output at rest
- About 1,800 L/day
- 10% of that --> filtrate
- 1% of filtrate (enters the nephron and has the ability to exchange material) --> urine
Anterior and posterior branches
Segmental aa --> Renal segments
- Surgically resectable
Right Renal Vein << Left Renal Vein
Right Renal Artery >> Left Renal Artery
Right kidney has shorter renal vein than left kidney
Superior mesenteric artery can put pressure on the renal vein and can even occlude blood flow - called nutcracker syndrome - compromises the tissue of the testis and ovaries as well
Right kidney artery is longer than left kidney artery
Renal Segments
Superior and inferior segment and in-between these segments have anterior superior and anterior inferior and a posterior segment (posterior in the back of anterior superior and anterior inferior)
Each part is surgically receptible - can remove on...
Superior and inferior segment and in-between these segments have anterior superior and anterior inferior and a posterior segment (posterior in the back of anterior superior and anterior inferior)
Each part is surgically receptible - can remove one without harming the other segments
Kidney Arteries
Segmental arteries --> Interlobar arteries --> Arcuate arteries --> Interlobular arteries --> Afferent arterioles
Segmental arteries flow into interlobar arteries which are nestled between the renal pyramids and columns - as they cross around the base of the pyramids they turn into arcuate arteries --> from there they turn into interlobular arteries (really small) then afferent arterioles (go into the capillaries of the glomerulus)
Blood Flow through Kidney
Renal Artery --> Segmental Arteries --> Interlobar Arteries --> Arcuate Arteries --> Interlobular Arteries --> Afferent Arterioles --> Glomerular Capillaries --> Efferent arterioles --> Peritubular Capillaries --> Interlobular Veins --> Arcuate Ve...
Renal Artery --> Segmental Arteries --> Interlobar Arteries --> Arcuate Arteries --> Interlobular Arteries --> Afferent Arterioles --> Glomerular Capillaries --> Efferent arterioles --> Peritubular Capillaries --> Interlobular Veins --> Arcuate Veins --> interlobar Veins --> Renal Vein
How the Nephron Works
1. Glomerular Filtration - moving blood from glomerulus into the nephron itself
2. Tubular Reabsorption - when we take material that are in the urine that we want to reclaim back into the blood
3. Tubular Secretion - what we want to get rid of i...
1. Glomerular Filtration - moving blood from glomerulus into the nephron itself
2. Tubular Reabsorption - when we take material that are in the urine that we want to reclaim back into the blood
3. Tubular Secretion - what we want to get rid of in the blood we secrete out
Afferent arterioles go into glomerular capsule (glomerular capsule + glomerulus = renal corpuscle)
Glomerular Filtration
150-180 liters day (65x blood plasma volume)
1-2 L of urine daily
Filtration membrane (endothelial-capsular membrane)
Mesangial cells - smooth muscle cells
- Extraglomerular - regulate blood pressure (RAA)
- Intraglomerular - regulate glomerular filtration rate
Renal Corpuscle
Glomerular capsule + glomerulus
Bunch of cells called podocytes - help regulate the movement of material out of the capillaries and into the capsule that will then become filtrate
Filtration Membrane
Three Filters
- Fenestration (pore) of Glomerular Endothelial Cell: prevents filtration of blood cells
- Basal Lamina of Glomerulus: prevents filtration of larger proteins
- Slit Membrane Between Pedicels: prevents filtration of medium-sized proteins
Cortical Nephron
Renal corpuscles lie in the outer portion of the renal cortex - loops lie mainly in the cortex and penetrate only into the outer region of the renal medulla
Ubiquitous - found everywhere
Shorter nephron loops
Lower GFR
Juxtamedullary Nephron
Less common
Higher GFR
Longer nephron loops - extend into the deepest region of the medulla
- thin/thick limbs (two different portions - both ascending limbs), vasa recta (receive blood from here)
More concentrated urine
Glomerulonephritis (GN)
Inflammation of kidney (glomeruli)
Suite of diseases
- Common: allergic reaction to Strep. toxins (IgA nephropathy, aka Berger's disease)
Filtration membranes pass blood and protein
Hematuria, possibly proteinuria
May lead to chronic renal failure (25-35%)
Proximal Convoluted Tubule
Major site of reabsorption**
  - Salts and H2O (~66%), glucose and amino acids (100%), citrate (~80%), PO4 3- (~80%), K+ (~65%), Urea (~50%) - all of these move back into the blood
Two regions: pars convoluta (allows things back into the blood) ...
Major site of reabsorption**
- Salts and H2O (~66%), glucose and amino acids (100%), citrate (~80%), PO4 3- (~80%), K+ (~65%), Urea (~50%) - all of these move back into the blood
Two regions: pars convoluta (allows things back into the blood) and pars recta (allows things out)
Things that go out of blood: medications, NH4+
In order to move water across a membrane, need to set up an osmotic gradient - move sodium and then water follows the sodium
Nephron Loop (of Henle)
Enter nephron loop from the proximal tubule
Two distinct regions: descending loop and ascending loop
  Descending - reabsorb water
  Ascending - reabsorb salts (NaCl)
Bottom portion where it is thinner is more passive and upper portion where i...
Enter nephron loop from the proximal tubule
Two distinct regions: descending loop and ascending loop
Descending - reabsorb water
Ascending - reabsorb salts (NaCl)
Bottom portion where it is thinner is more passive and upper portion where it is thicker have more active movement
Specialized vessels called vasa recta - vessels that are straight and they set up a counter-current exchange as to extract water from the loop of Henle as best as possible - allows us to have more concentrated urine by absorbing water out - important for desert-dwelling organisms
Juxtamedullary nephons have vasa recta too
Distal Convoluted Tubule and Collecting Ducts
Both reabsorption and secretion
- Absorb water - vasopressin works on principle cells
- Absorb Ca2+
- Move sodium back in as a response to more water - modulated by aldosterone
Opportunity to use the kidneys to help regulate pH - secrete and/or absorb HCO3 and H+ - help maintain pH
Juxtaglomerular Apparatus
Regulates renal blood flow and GFR which is also important to blood pressure**
Macula densa (good chemoreceptors - can detect the ratio of certain solue namely salts/water in urine and act accordingly in respect to the body) --> paracrine vasopressor
Juxtaglomerular cells --> renin
Proximal to the distal tubule
Mesangium cells - extraglomerular (found outside can help regulate pressure in the arterioles) intraglomerular (can regulate filtration rate)
Diuretics
Slow renal reabsorption of water via diuresis
Reduce blood volume
Treat hypertension
Caffeine (increases glomerular filtration rate)
Alcohol (inhibits ADH production)
- 1 g. consume --> urine excretion increase ~10 mL
Renal Failure
Acute
Chronic
Acute Renal Failure (ARF)
Suppression of urine flow
- Oliguria: daily urine output 50-250 mL
- Anuria - daily urine output < 50 mL
- Low blood volume, damaged tubule, allergic reaction, trauma, etc.
Chronic Renal Failure (CRF)
Progressive and irreversible
End stage: 90% of nephrons lost, GFR 10-15% of baseline
Require dialysis or transplant (if they don't have compensation from the other side)
Can manage with one kidney
Dialysis
Hemodialysis - blood filtered by machine
Continuous Ambulatory Peritoneal Dialysis (CAPD) - peritoneum used as a filtration membrane
- Sterile dialysis solution collects waste products in the peritoneum, then is drained
Urine Transport
Bilateral uterers: length - 25-30 cm diameter - 1-10 mm
Layered
- Adventitia
- Muscularis
- Mucosa: transitional epithelium + lamina propria
Peristalsis, hydrostatic pressure, gravity
- Peristaltic waves 1-5 per minute
- Innervated by the renal plexus
Physiolgical valve (pressure) distally
From the minor calyces --> major calyces --> pelvis --> ureters --> transported down to urinary bladder
Ureter Histology
Different layers of the tissue - innermost layer is transitional epithelium (distensible - can be stretched)
Layer of smooth muscle (muscularis) - squeezes urine downwards (though most of it is done through gravity) - important for moving kidney stones
Urine Transport and Storage
Urine will end up in urinary bladder - has extreme amount of smooth muscle - can expand or contract depending on conditions
Trigone - formed by where the ureter opens
Internal Urethral Orifice - has sphincter and enters the urethra (where urine comes out) afterwards
Urethral openings have no sphincters on them but there are physiological valves to close them off - when the bladder fills up to 300-400 mL it will tip backwards and will seal off the openings so urine doesn't flow back up into the urethra - have specialized bear receptors that will let you know when you have to go
Female Pelvis
Urinary bladder 
Urethra - generally located just external to the vagina posterior to the clitoris (sometimes inside which is not uncommon)
Urinary bladder
Urethra - generally located just external to the vagina posterior to the clitoris (sometimes inside which is not uncommon)
Urinary Bladder
Average capcity = 700-800 mL
Trigone
Internal urethral orifice and sphincter (smooth)
External urethral sphincter (skeletal muscle)
Vesical (superior, middle, inferior) arteries
Innervation:
- Nerves from hypogastric plexus
- Pelvic splanchnic nerve (S2 and S3)
Micturition
S2 & S3 segments = micturition center
Micturition Reflex
- 200-400 mL --> baroreceptor activation
- S2 & S3 segments = micturition center
- Parasympathetic --> detrusor contraction and internal uretrhal sphincter relaxation (this is where you'll make a decision consciously to slench that skeletal muscle sphincter)
- Inhibits SMNs to external urethral sphincter
- May be voluntarily halted
Cortical control too
Incontinence
Lack of voluntary control over micturition reflex
Normal in children under 2-3
Stress incontinence: young females
- Weak pelvic floor musculature
Urge incontinence: elderly
- Irritation of urinary bladder
Overflow Incontinence - involuntary leakage
Functional incontinence
Female Urethra
~4 cm
External urethra orifice typically between the clitoris and vagina
Layered:
- Muscularis
- Mucosa: epithelium and lamina propria
- Transitional --> Columnar --> Stratified squamous epithelium
Male Urethra
~20 cm
Urine and semen
Three regions:
- Prostatic urethra: through prostate
- Membranous (intermediate) urethra: under perineal muscles
- Spongy urethra: through penis
Glands: prostate, seminal vesicles, bulbourethral (Cowper's) glands, and urethral (Littre) glands
Differences between Male and Female Urethra
Females have dedicated urethra only for urine - males urethra serves as a place for urine and gametes - males have prostate gland and seminal vesicles which secrete components for semen which are delivered up through the vas deferens where they are stored waiting for ejaculation
Men and women have different regions of the urethra
Women are more susceptible to UTI - shorter urethra which is also closer to the rectum
Urinalysis
95% water
5% solutes
- Urea, ions, metabolic wastes
Development of Urinary System
Mesoderm --> intermediate mesoderm (located on the urogenital ridges - kidneys and gonads come from intermediate mesoderm)
Pronephros (and pronephric duct) - degenerates and disappears @ 6th week
Mesonephros (and mesonephric duct) - degenerates and disappears @ 8th week
Mesonephric duct --> Uteric bud
Metanephros
Cloaca --> urogenital sinus and rectum
Three kidneys develop: prnephros, mesonephros, and metanephros (sticks around)
Gonads and kidneys develop from the same source of tissue**
Abnormalities of Development of Urinary System
Unilateral renal agenesis (1/1,000 births, males)
Malrotated kidneys
Ectopic kidney
Horseshoe kidney
Aging and the Urinary System
kidneys decrease in size with age
blood flow and filtration decreases
- Rates decline 50% between age 40-70
- At 80, only 60% of glomeruli are functioning
Polyuria, nocturia, dysuria
Incontinence
Hematuria
Digestive System Anatmoy
Muscular tube open at both ends with attached accessory structures - two major parts
- Gastrointestinal Tract
- Accessory Digestive Organs
Gastointestinal Tract (Alimentary Canal)
Oral cavity --> Pharynx (oro + laryngo) --> Esophagus --> Stomach --> Small Intestine --> Large Intestine
Accessory Digestive Organs
Teeth, tongue, salivary glands, gall bladder, liver, pancreas
GI Tract Functions
Mouth - bite, chew, swallow
Pharynx and esophagus - transport
Stomach - mechanical disruption; absorption of water and alcohol
Small Intestine - chemical and mechanical digestion and absorption
Large intestine - absorb electrolytes and vitamins (B and K)
Rectum and anus - defecation
Layers of the GI Tract
Mucosal layer - helps to lubricate - humidifes the air keeping the mucosa from cracking and letting pathogens in
Submucosal layer - may have blood vessels running through
Muscularis layer - two layers - longitudinal and circular muscle fibers all through GI tract
- Circular ones act like sphincters - mouth is the first sphincter - help squeeze food through
Parasympathetic - digestion and sex
Sympathetic - running, heart rate increase, increase airflow in lungs
Serosa layer - has serous fluid that allows things to slip around (don't want them sticking together)
Peritoneum
Double-layer serous membrane covers some of the digestive system structures = 2 layers
- Parietal layer: lines abdominopelvic wall and folds back on itself forming a double membrane = mesentary - lines the walls of body cavity
- Visceral Layer - covers organs
Peritoneal Cavity - potential space containing a bit of serous fluid
Functions of Mesentary (parietal layer of peritoneum)
Supports the intestines = mesocolon; stomach = omenta: and liver = falciform ligament
Prevents intestinal twisting
Stores fat
Pathway for blood vessels and nerves
Greater Omentum
type of mesentary - (mesentary = folds of serous membrane that connect the organs to the cavity wall)
grows faster than normal
the more fat you put on your body, the more blood vessels you have to make and then your heart has to work harder to p...
type of mesentary - (mesentary = folds of serous membrane that connect the organs to the cavity wall)
grows faster than normal
the more fat you put on your body, the more blood vessels you have to make and then your heart has to work harder to pump blood through the body
Only attached through the transverse colon and the stmoach
Lesser Omentum
attaches the stomach to the liver
Ligament - describes an attachment of one organ to another organ by some sort of connective tissue
Peritonitis
Acute inflammation of the peritoneum
Cause: contamination by infectious microbes during surgery or from rupture of abdominal organs
Oral Cavity (Buccal Cavity) - Mouth
Lined with epithelium - non-keratinized stratified epithelium - withstands abrasion from masticated food
Buccinator - innervated by facial nerve
Boundaries
- Anterior = lips (labia) --> orbicularis oris mm - mucus membrane on inner surface - lips attached to gums by labial frenulum
- Lateral = cheeks = formed by buccinator mm. - covered by mucus membrane on inside
- Superior = palate (hard = maxillary bone & soft = skeletal mm)
- Inferior = tongue - accessory digestive organ (2/3 oral cavity - anchored by lingual frenulum) (1/3 oropharnyx)
Tongue
Rough due to Papillae (three types)
1. Filliform - cone-shaped, smallest, no taste buds, most abundant type, friction for licking
2. Fungiform - mushroom-shaped, well-vascularized (red tongue), has taste-buds
3. Vallate - 12 large papillae, inverted "V" shape, back of tongue, has taste buds
Chemoreceptors
Olfactory (smell) and gustatory (taste): for receptors to work, chemicals must be volatile and soluble in water
Olfactory epithelium - top of nasal cavity at the bottom of the ethmoid bone - olfactory foramina allows neurons to get to the olfactory bulbs on the brain
Location of olfactory receptors:
1. Olfactory epithelium 2. Olfactory receptor cells 3. Supporting cells 4. Basal cells 5. Olfactory sensory fibers
Special Senses
Chemoreceptive Senses
responsive to chemicals in aqueous solution
Taste
Taste
Location of taste buds
- Oral cavity, 10,000 buds on infant tongue, papillae (3 forms - filiform, fungiform, circumvallate)
Structure of Taste Buds
Gustatory Hairs
Gustatory Pores
Gustatory Taste Cells
Basal Cell
Sensory Nerve Fiber
Series of cells that help papillae for taste - know general idea that there are different taste receptors buried in various papillae and are useful for tasting different things
Taste Sensations - Receptors
1. Sweet 2. Salty 3. Sour 4. Bitter [Water Receptors and Umami Receptors]
Sweet and salty at the front of the tongue
Umami receptors - good for savory things [MSG binds well with theses]
Can have receptors all over the place
1. Sweet 2. Salty 3. Sour 4. Bitter [Water Receptors and Umami Receptors]
Sweet and salty at the front of the tongue
Umami receptors - good for savory things [MSG binds well with theses]
Can have receptors all over the place
Teeth
Mastication
4 types:
- Incisors (8) for cutting
- Canines (4) tearing and piercing
- Premolars (8) grinding and crushing
- Molars (12) grinding and crushing
32 teeth total in adult
Baby Teeth
milk teeth are temporary
Incisors: 8
Canines: 4
Molars: 8
20 total teeth
Premolars are missing in children - mandible isn't big enough for all adult teeth
Dental Formula
Divide mouth into four quadrants
Top Row: 2 1 2 3
Bottom Row 2 1 2 3
Order (l -> r) I; C; P;M
Teeth Structure
Pulp cavity
Dentin
Enamel

Gingivitis - bacterial infection of gums
Plaque - sticky matrix on surface of teeth made by bacteria + trapped food particles - if hardens - tartar
Pulp Cavity
center of tooth; receives BV's and nerves from the root canal (narrow tunnel at base of tooth) which support and nourishes the dentin
Dentin
non-living boney matrix of tooth
- Largest portion of tooth
- Surrounded by enamel
Enamel
above the gum (gingiva) line only
- Hardest known biological substance made of calcium phosphate crystals (Vitamid D and Calcium)
Salivary Glands Composition
Fluid = Saliva
pH = 7.0
1-1.5 L/day
Composition
1. 97% water 2. Immunoglobulin A, 3. Lysozyme 4. Na+, K+, HCO3-, Cl- 5. Amylase: digestive enzyme breaks down sugars 6. Mucus
Swallowing reflex is inhibited when you are asleep - breathing and vomiting can happen during sleep - do not make saliva while you are asleep
Drooling because there is still saliva in your ducts when you fall asleep
Salivary Glands Function
1. Cleanse mouth
2. Antibacterial
3. Carbohydrate digestion started
4. Aids in chewing and swallowing
Salivary Glands Types
Intrinisic = inside oral cavity
- buccal glands
Extrinsic = 3 types - outside oral cavity and connected by salivary ducts
1. Parotid
2. Submandibular
3. Sublingual
Parotid - Extrinsic Salivary Gland
Largest
Infected with Myxovirus = mumps
Parotid (Stensen's) Duct = connection to oral cavity
Adult males with mumps = sterilization
If mumps were to afflict us now, we could get pancreatitis which could lead to diabetes
Submandibular - Extrinsic Salivary Gland
Beneath mandible - found on the angle of the mandible - gland will fall down to the neck that looks like jowels - classic gleaking gland (saliva will come shooting out of it)
Submandibular (Wharton's) ducts
Sublingual - Extrinsic Salivary Gland
Under tongue - found between your lower gum of the mandible and the base of your tongue - 12-18 ductules that drain that gland up to the mouth
Sublingual (Rivinus') Ducts
Oropharynx - common to both the respiratory and digestive system
Physiology of the Esophagus - Swallowing
Voluntary phase - tongue pushes food to back or oral cavity
Involuntary phase - pharyngeal stage
- Breathing stops and airways are closed
- Soft palat and uvula are lifted to close off nasopharynx
- Vocal cords close
- Epiglottis is bent over airway as larynx is lifted
Swallowing
Upper sphincter relaxes when larynx is lifted
Peristalsis pushes food down
- Circular fibers behind bolus
- Longitudinal fibers in front of bolus shorten the distance of travel
Travel time is 4-8 seconds for solids and 1 second for liquids
Lower phincter relaxes as food approaches
Peristalsis
Wave-like contractions of the smooth muscle tissue
Gastro-esophageal Junction
Way for gases to come back up - burps
Escape mechanism for these gases
Phreno-esophageal Ligament - allows the stomach to move up when it tears - causes hernias which is an unnatural opening in a muscle
Hernias
Acid rich - cause heartburn
Sliding hiatus hernia - most common
If you pinch off the blood supply to the fundus (dome) then it can rupture and that's bad - may try to push it back down through surgery
Symptoms of hernias: heartburn, metallic taste in mouth, wet burps
Esophogeal Cancer - cut it out - pull stomach up and attach it to the base of the throat and eat that way
Complications of Peptic Reflux
Peptic esophagitis
Inflammation of esophageal wall
Ulceration
Stomach
Body of the stomach - where most digestion happens
Constriction - junction between the end of the stomach and the duodenum - causing the restriction is a strong sphincter called the pyloric sphincter
Duodenum is not well developed to deal with a lot of acid coming through which is the necessity of the pyloric sphincter
Historical Perspective of Stomach
Martin - patient of Beaumont - look into his stomach any time he wanted to
For years Beaumont studied him to figure out the function of the stomach
Stomach stores food for about 4 hours, while it is storing it is breaking it down using pepsin and other acids, and mechanically mixing it
Muscularis Externa
3 mm layers
1. Outer = longitudinal
2. Middle = Circular
3. Inner = Oblique
Helps to undulate the food and mechanically mix it with the acids that are in there
The nerve that controls this parastaltically? - vagus nerve (epiglottis controlled by vagus as well)
Vagus controls first 2/3s of large intestine as well
Vagus also slows down your heart and constrict airways in your lungs
Gastric Rugae
Mucosa + Submucosa
Inside the stomach are rugae
Present when stomach is empty and go away when the stomach expands
Don't confuse rugae with the gastric pits - gastric pits are microscopic while rugae are macroscopic - you can see them when the stomach is empty
Gastric Pits
Have to distend the stomach to see them
Some are called parietal calls (make hydrochloric acid and intrinsic factor which helps with B12 absorption which helps with new red blood cell production)
Chief cells make pepsin which is an enzyme that helps digestion of proteins
Gastric Emptying
slow process
- Gastrin and PSN Promotes; SNS inhibits
4 hours to empty after eating
Food lingers in stomach the longest of GI organs
Food --> Chyme
Chyme emptied to duodenum via pyloric sphincter
Chronic Gastric Ulcer
Causes: hydrochloric acid, pepsin
Helicobacter pylori
Hepatic Portal Triad
Vein, common bile duct, artery
Omental Bursa
Stomach: transverse colon attached to the greater omentum
Bed of the stomach is the pancreas because it's blocked by the stomach and spinal column and ribs behind it
Tranverse mesocolon hangs from the spleen - ribs - 8; blood balloon - capsule ruptures very easily - most common for internal bleeding
Gastric Arteries
Lots of vascularity to stomach
Lipid soluble enter the blood system
Celiac trunk branches to other organs: splenic artery (supplies the spleen and major tributary to the pancreas) liver and gall bladder from proper hepatic
Stomach is a foregut organ through middle of duodenum
Gastric Veins
Veins that parallel the arteries
Hepatic portal vein and is the key goal for blood drainage from the gut to the capillaries then to the hepatic vein on top of liver then to the inferior vena cava
Splenic vein contribute to the hepatic portal vein
Superior mesenteric vein contribute to the hepatic portal
Inferior and superior messenteric vein (high gut = inferior, mid gut (first 2/3 of the intestin) = superior)
Superior Mesenteric Artery and Vein
both come from under the pancreas
Mechanical Digestion - Physiology
Gentle mixing waves - every 15-25 seconds - mixes bolus with 2 quats/day of gastric juice to turn it into chyme ( a thin liquid with nutrients)
More vigorous waves - travel from body of stomach to pyloric region
Intense waves near the pylorus - open it and squit out 1-2 teaspoons full with each wave
Major enzyme - pepsin which works well in the presence of hydrochloric acid
Chemical Digestion - Physiology
Protein digestion begins
- HCl denatures (unfolds) protein molecules
- HCl transfoms pepsinogen into pepsin that breaks peptides bonds between certain amino acids
Fat digestion continues
- Gastric lipase splits the trigktcerides in milk fat
- Most effective at pH 5-6 (infant stomach)
Hcl kills microbes in food
Mucous cells protect stomach walls from being digested with 1-3 mm thick layer of mucous
Cephalic Phase
"Stomach Getting Reading"
Cerebral cortex - sight, smell, taste, and though
- Stimulate paraympathetic nervous system
Vagus nerve
- Increases stomach muscle and glandular activity (fore gut and mid gut; not hind gut)
Sympathetic and Paraympathetic Neurotransmitters
sympathetic neurotransmitter - inhibit digestion
paraympathetic neurotransmitter - cause digestion to increase
Acetylcholine (in muscles) - gastric motility and secretion
Vagus nerve ends when you get to the large intestine
Sympathetic everywhere in body but parasympathetic only near spinal chord
Absorption of Nutrients by the Stomach
Water especially if it is cold
Electrolytes
Some drugs (especially aspirin) and alcohol
Fat conent in the stomach slows the passage of alcohol to the intestine where absorption is more rapid
Gastric mucosal cells contain alcohol dehydrogenase that converts some alcohol to acetaldehyde - more of this enzyme found in males than females
Females have less total body fluid that same size male so end up with high blood alcohol levels with same intake of alcohol
Vomiting (Emesis)
Forceful expulsion of contents of stomach and duodenum through the mouth
Cause:
Irritation or distention of stomach
Unpleasant sights, general anesthesia, dizziness and certain drugs
Sensory input from medulla cause stomach contraction and complete sphincter relaxation
Contents of stomach squeezed between abdominal muscles and diaphragm and forced through open mouth
Serious because loss of acidic gastric juice can lead to alkalosis
Small Intestine
Convoluted Tube - length varies with muscular tone
Longest part of GI; smallest in diameter
Extends from Pyloric Sphincter --> Ileocecal valve
Diameter - 2.5 cm
3 Regions: Duodenum, jejunum, ileum
Duodenum
10 in. long: superior part (retroperitoneal)
3 accessory organs associated
- Pancreas (Pancreatic duct)
- Gall bladder (Cystic D.)
- Liver (Hepatic D.)
Features
Brunner's Glands - makes alkaline mucus that neutralizes chyme
Purpose - absorption
Jejunum
Smaller than duodenum because more absorption that occurs less comes out
Liver - Characteristics and Key Functions
Largest internal organ
4 Lobes: Right and left lobes anchored by falciform ligament; Caudate and Quadrate (underside)
Digestion:
- Bile production (alkaline yellow-green fluid): break down heme
- Bile salts (cholesterol derivative): emulsify (break droplets apart) large fat globules for enzyme attack
Functions of Liver
Destroys or store toxins
Remove foreign debris or old RBC's, hormones in circulation, antibodies
Plasma protein synthesis (hepatocytes)
Albumin - #1 protein in blood (WBC)
Gallbladder - Characteristics and Functions
Muscular, greenish sac attached to liver (ventral side)
Stores and concentrates bile (released thru Cystic duct)
Common Bile Duct + Pancreatic Duct = Hepatopancreatic Ampulla --> Duodenal Papilla
Opening is controlled by Hepatopancreatic Sphincter (Sphincter of Oddi)
The hormone Cholecystokinin (CCK) Cx of gallbladder and releases Sphincter of Oddi = releases bile and pancreatic juices to duodenum
Pancreas Characteristics and Functions
Tadpole shaped gland
Retroperitoneal
Endocrine Gland - insulin, glucagon, somatostatin - inhibits (islet cells)
Exocrine Gland - pancreatic juice (acini cells)
   - Water, HCO3-, amylase (starch digestion), lipase (fat digestion), endopeptidas...
Tadpole shaped gland
Retroperitoneal
Endocrine Gland - insulin, glucagon, somatostatin - inhibits (islet cells)
Exocrine Gland - pancreatic juice (acini cells)
- Water, HCO3-, amylase (starch digestion), lipase (fat digestion), endopeptidases (protein digestion) [ex. Chymotrypsin - cleaved from Chymotrypsinogen = zymogen)
Juices delivered to duodenum by merger of pancreatic duct with common bile duct --> duodenal papilla
Duct Pathways of Digestion System
Jejunum - Small Intestine Region
Middle portion
between duodenum and ileum
8 ft long
Larger lumen > ileum
absorption of nutrients
Ileum - Region of Small Intestine
Longest section of SI
Posterior portion
Terminates at the Ileocecal Valve (opens into the cecum of the LI)
Peyer's Patches (MALT) fight infection - within the walls of intestine
Structural Modification of Small Intestine
4 Tunics aid absorption
Plicae Circulares (circular folds)
Villi (finger=like)
Microvilli
All of these structures increase SA = 200 m2
Plicae Circulares (Circular Folds) Small Intestine
deep folds of mucosa and submucosa (1 cm tall) --> chyme spirals through - mixes with enzymes
Villi - Structural Modification of Small Intestine
projections of mucosa (simple columnar epithelium cells)
Anchored to lamina propria (BV's and LV's)
Narrow pouched between Villi - Intestinal Crypts - Deep in crypts are paneth cell - lysozyme
Microvilli
Hair-like projections of the cell membrane of villi
Brush Border - enzymes for protein, sugar, and carbohydrate digestion
Function of Small Intestine
Digestion
Absorption
- Monosaccharides, amino acids, water, lipids, vitamins, electrolytes
Ileocecal Region
Colon - part of large intestine
Cecum - first 6 inches
Appendix - full of MALT tissue for the large intestine
Large Intestine
Extends from Ileocecal Valve to Anus
Length - 5 ft; Diameter - 2.5 in
4 Regions:
- Cecum, Colon, Rectum, Anal Canal
Cecum - Region of Large Intestine
First region of large intestine
Sac-like portion beneath ileocecal valve
Appendix hangs from medial surface in lower right quadrant
MALT: traps enteric bacteria = infection = appendicitis
Appendix
Served by its own artery
Mucosa and Musculature of Large Intestine
Bands (haustra) are used for creation stronger peristaltic waves to move the condensed leftovers along
Splenic and hepatic flexure are located at the turns of the intestine
Colon - Region of Large Intestine
4 Subdivisions
1. Ascending colon: right side of abdominal cavity makes 90 degree turn under liver = hepatic flexure
2. Transverse colon: horizontal across abdominal cavity turns down under spleen = splenic flexure
3. Descending colon: down left side of abdominal cavity
4. Sigmoid Colon: S-shaped portion in pelvic cavity
Rectum - Region of Large Intestine
Continuous with sigmoid colon
Stores feces
Rectal valves: transverse folds separate feces from flatus (intestinal gas)
Colonic bacteria produce flatus from indigestible carbohydrates (beans, broccoli)
Stretching rectal walls initiates defecation reflex
Anal Canal - Regions of Large Intestine
Opens to exterior via anus
Lined with stratified squamous epithelium
2 Anal sphincters
- Internal Anal Sphincter (smooth mm) - involuntary
- External Anal Sphincter (skeletal mm) - voluntary
Structural Modification of Large Intestine
Structural modifications
- Muscularis Externa
- Haustra
- Epiploic Appendages
Muscularis Externa - Structural Modification of Large Intestine
Teniae coli "tiny ribbons" - 3 bands of smooth muscle
Function: produce powerful and long lasting peristalsis - moves large quantities of chyme to rectum (3x/day)
Haustra - Structural Modification of Large Intestine
Sac-like pouches of colon wall
Haustral Cx - slow segmentation of chyme (every 30 min) - mix, churn, and absorbs water and electrolytes from chyme
Epiploic Appendages
Fat-filled bags hanging from serosa
Function - unknown
Function of Large Intestine
Formation of feces from indigestible materials
Absorption of vitamin K, B, and 1800 mL of water/day
200 mL of H2O in feces