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107 Cards in this Set

  • Front
  • Back

The "Cambrian explosion" refers to

the origination of all major phyla of animals.

How do scientists believe that an asteroid impact in the Yucatan peninsula of Central America caused a worldwide mass extinction?

by blocking the sun and inhibiting photosynthesis

Hominids include

All answers are correct.

The closest living relatives to humans on the evolutionary tree are


Scientists use mitochondrial DNA to track the migration of humans across the planet. After a group migrates away from their ancestral homeland, any mutations that occur are not mixed with those left in the ancestral population. Therefore, mitochondrial DNA samples taken from ____ would have the fewest unique mutations, representing the original and oldest DNA sequences.


An invertebrate is an animal that

does not have a backbone.

A vertebrate is an animal that

has a backbone.

Which of the following characteristics do all animals share?

They are multi-cellular eukaryotes.

Which of the following is NOT a characteristic of animals?

They have cell walls.

The type of body symmetry in which any plane passing through the body from the mouth to the opposite end divides the body into mirror images is

radial symmetry.

An animal with only one opening to take in food and eject waste has a

incomplete digestive tract.

The type of body symmetry in which only one plane divides the body into mirror images is

bilateral symmetry.

Sponges belong to the phylum


Corals and jellyfish belong to the phylum


All cnidarians share the ability to do which of the following?

sting predators and prey

Snails and squids belong to the phylum


Leeches and earthworms belong to the phylum


Spiders and scorpions belong to the phylum


Sea cucumbers and sea urchins belong to the phylum


A complete digestive tract has both a mouth and an anus and the food passes in one direction from the mouth to the anus.


Sea cucumbers belong to the plant kingdom.


Mammals that lay eggs are marsupials.


Animals are very diverse. Which of the following is NOT an animal?


A preparation that "teaches" the immune system to recognize a disease-causing agent without actually causing disease is termed a(n)


A molecule that stimulates an immune-system reaction by B cells and T cells is termed a(n)


A phagocyte is a

cell that engulfs other cells and debris.

Which of the following is not part of the innate defense response?

antibody production

Physical and chemical barriers that form the first line of innate defense include

All answers are correct.

The innate chemical substance produced by basophils that causes blood vessels to dilate is


Which of the following is a reason why fever is considered a defense mechanism?

All answers are correct.

A Y-shaped protein that is produced in response to a specific antigen and recognizes these antigens is a(n)


A primary "antigen presenting cell," a cell that presents an antigen to a helper T cell, is a


Which of the following are examples of passive immunity?

a fetus acquiring antibodies through the placenta, or a person receiving an injection of antibodies

Which of the following are examples of active immunity?

only antibodies produced from a vaccine

The region of an antibody molecule that recognizes and binds to an antigen is the

variable region.

In a process called ______, an army of plasma cells and memory cells are produced from properly-stimulated B cells.

clonal selection

The primary function of a vaccine is to

create immunological memory without causing disease.

HIV-positive people track the progress of their disease with blood tests that measure the number of

helper T cells.

An exaggerated attack on a harmless antigen by an overly-sensitive immune system is termed a(n)


In an autoimmune disease, the immune system attacks the body's "self antigens."


A fever has no defense function, but acts only as a sign that an infection is present in the body.


The type of T cell that is primarily responsible for the production of antibodies is the plasma cell.


The constant region of an antibody molecule determines which antigen will be bound by the antibody.


The primary immune response produces memory cells that stimulate a faster immune response on a subsequent exposure to the same foreign antigen.



All answers are correct.

The large vessels of the circulatory system that carry blood away from the heart are


The large vessels that carry blood to the heart are


The small vessels from which water and dissolved substances diffuse between the blood and interstitial fluid are


Vertebrates with a three-chambered heart include


The upper chambers of the mammalian heart are the


Which of the following is an artery that supplies blood to the heart muscle?

coronary artery

A heartbeat begins in the

sinoatrial node.

At the capillaries, ___________ leaves red blood cells and _____________ enters the circulation.

oxygen; carbon dioxide

Blood pressure is

the force that blood exerts on the walls of the arteries.

The instrument that measures blood pressure is the


Systolic pressure reflects the force caused by

the contraction of the ventricles.

Diastolic pressure reflects

the relaxation of the ventricles.

The liquid matrix of blood is


The cellular components of blood that transport oxygen are

red blood cells.

The cellular fragments that help in initiating blood clotting are


The protein found in red blood cells that transports oxygen is


The small air sacs of the lungs are the


The ______ system brings in oxygen to the body, and the oxygen is transported to the cells by the ______ for aerobic respiration.

respiratory; circulatory

The human circulatory system transports blood in a one-directional circuit throughout the body.


The sinoatrial node sets the tempo of the heart beat.


The device that is used to measure a person's blood pressure is a sphygmomanometer.


The division of the nervous system that integrates sensory information and coordinates the body's response is the

central nervous system.

The rounded part of a neuron containing the nucleus and mitochondria is the

cell body.

The part of the neuron that is usually highly branched and receives input from other neurons is the


The part of the neuron that is usually a single long extension that conducts an impulse to a muscle or another neuron is the


The junctions between one neuron and another neuron are called


Usually the ________________ conducts nerve impulses from the cell body to a muscle, gland, or another neuron.


The three types of neurons in the nervous system of humans are

sensory neurons, interneurons, and motor neurons.

The type of neuron that conducts its message from the central nervous system toward an effector is the

motor neuron.

The type of neuron that connects one neuron to another within the central nervous system is the


Usually nerve impulses travel from one neuron to another by


A chemical that travels from a sending neuron to a receiving neuron is called a(n)


The division of the peripheral nervous system that carries signals to voluntary muscles is the

somatic system.

The part of the central nervous system that conducts information to and from the brain is the

spinal cord.

The nervous tissue that consists of myelinated axons transmitting information throughout the central nervous system is the

white matter.

The part of the brain that controls the qualities of what we consider the "mind" is the


Which of the following best describes how a neuron fires?

Na+ ions cross the plasma membrane initiating a wave that travels down the axon.

A neuron recharges when

Na+ ions are actively pumped against their concentration gradient.

Rod cells provide color vision and allow us to see at night.


In humans, taste buds are most highly concentrated on the inside surface of the lips of the mouth.


Odorous molecules are first detected in the nose, are transduced and travel to the olfactory bulb and then to the cerebral cortex.


You are lying on a sand dune looking over the water, listening to the waves, and enjoying the feel of the sun and wind on your skin. You smell some chocolate chip cookies your friend is munching on. When you sit up to grab a handful you feel momentarily dizzy.When you look at the cookies, which of the following is being activated?


You are lying on a sand dune looking over the water, listening to the waves, and enjoying the feel of the sun and wind on your skin. You smell some chocolate chip cookies your friend is munching on. When you sit up to grab a handful you feel momentarily dizzy. When you look at the water, which of the following is being activated?


The process that unites the male gametes with the female gametes in organisms that reproduce sexually is termed


The diploid first cell of a new organism is a(n)


In the male, the sac-like structure that contains the testes is the


The tightly coiled structure (structures) inside the testes that produce the sperm cells is (are) the

seminiferous tubules.

In the male, the tube that extends from the scrotum to the point of connection with the urethra is the

vas deferens.

The structure that secretes a thin, milky, alkaline fluid that activates the sperm to swim is the

prostate gland.

Which of the following is NOT a component of a sperm cell?


The cap-like __________________ covers the head of the sperm and releases enzymes that will help the sperm penetrate the egg.


Cilia sweep the released mature oocytes from ovaries into the

uterine tubes.

The muscular sac-like organ of the human female in which the fetus develops is the


Fertilization of a secondary oocyte normally occurs in the

fallopian tube.

In a secondary oocyte, meiosis is arrested in metaphase II until

fertilization occurs.

The surge of the hormone _______________ in the bloodstream of the female triggers ovulation.


The structure that connects the embryo to the placenta is the

umbilical cord.

Birth control pills contain a combination of estrogen and progesterone. How would this prevent pregnancy?

It would prevent ovulation.

Often a woman may first suspect she is pregnant when she misses a period or menstrual cycle. Why is it important for the menstrual cycle to be blocked during a pregnancy?

to prevent the blastocyst from being lost

Ovulation is triggered by a surge of LH in the bloodstream.


The intake of alcohol, cigarette smoke, and insufficient amounts of vitamins may all cause birth defects in a developing fetus.


The events of the birthing process use positive feedback. The stretching of the cervix during pre-labor or stage 1 of labor causes the hypothalamus to trigger the pituitary gland to release the hormone oxytocin, which causes uterine contractions.