2) Circulatory systems have the primary benefit of overcoming the shortcomings of
A) temperature differences between the lungs and the active tissue.
B) the slow rate at which diffusion occurs across cells.
C) communication systems involving only the nervous system.
D) having to cushion animals from trauma.
E) fetal organisms maintaining an optimal body temperature.

B

9) In which of the following organisms does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body?
A) annelids
B) molluscs
C) fishes
D) frogs
E) insects

D

10) The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the
A) amphibians.
B) birds.
C) fishes.
D) mammals.
E) reptiles.

C

15) After several weeks of exercise, a human athlete's resting heart rate is typically lower than before because
A) the body needs less oxygen than before.
B) the body temperature has increased.
C) the stroke volume has increased.
D) the cardiac output has decreased.
E) the body produces less carbon dioxide than before.

C

26) Among the following choices, which organism likely has the highest systolic pressure?
A) mouse
B) rabbit
C) human
D) hippopotamus
E) giraffe

E

27) Small swollen areas in the neck, groin, and axillary region are associated with
A) increased activity of the immune system.
B) a broken limb.
C) blood sugar that is abnormally high.
D) dehydration.
E) sodium depletion.

A

37) The diagnosis of hypertension in adults is based on the
A) measurement of fatty deposits on the endothelium of arteries.
B) measurement of the LDL/HDL ratio in peripheral blood.
C) percent of blood volume made up of platelets.
D) blood pressure being greater than 140 mm Hg systolic and/or >90 diastolic.
E) number of leukocytes per mm3 of blood.

D

82) A group of students was designing an experiment to test the effect of smoking on grass frogs. They hypothesized that keeping the frogs in a smoke-filled environment for defined periods would result in the animals developing lung cancer. However, when they searched for previously published information to shore up their hypothesis, they discovered they were quite wrong in their original assessment. Even though they were never going to go ahead with their experiment (so as not to harm frogs needlessly), they knew that a more likely outcome of putting carcinogens in the air would be the development of
A) the amphibian equivalent of hypertension.
B) skin cancer.
C) gill abnormalities in the next generation of tadpoles.
D) tracheal tube abnormalities.
E) diminished absorption of oxygen.

B

85) Pulse is a direct measure of
A) blood pressure.
B) stroke volume.
C) cardiac output.
D) heart rate.
E) breathing rate.

D

86) When you hold your breath, which of the following blood gas changes first leads to the urge to breathe?
A) rising O₂
B) falling O₂
C) rising CO₂
D) falling CO₂
E) rising CO₂ and falling O₂

C

53) Winter hibernation and spring reproduction in bears are cued by seasonal changes in the secretion of
A) melatonin from the pineal gland.
B) melatonin from the hypothalamus.
C) thyroxine from the anterior pituitary gland.
D) acetylcholine from the pineal gland.
E) thyroid-stimulating hormone from the posterior pituitary gland.

A

61) Estradiol is an example of
A) an androgen.
B) an estrogen.
C) a progestin.
D) a catecholamine.
E) a glucocorticoid.

B

62) Epinephrine is an example of
A) an androgen.
B) an estrogen.
C) a progestin.
D) a catecholamine.
E) a glucocorticoid.

D

67) Among these contraception methods, the highest risk of accidental pregnancy accompanies
A) the use of a diaphragm.
B) the use of a condom.
C) the practice of coitus interruptus.
D) a verified vasectomy.
E) the practice of the "rhythm method."

C

87) Which of the following characterizes parthenogenesis?
A) An individual may change its sex during its lifetime.
B) Specialized groups of cells grow into new individuals.
C) An organism is first a male and then a female.
D) An egg develops without being fertilized.
E) Both mates have male and female reproductive organs.

D

3) The nucleus and most of the organelles in a neuron are located in the
A) dendritic region.
B) axon hillock.
C) axon
D) cell body.
E) axon terminals.

D

6) The point of connection between two communicating neurons is called
A) the axon hillock.
B) the dendrite.
C) the synapse.
D) the cell body.
E) the glia.

C

7) In a simple synapse, neurotransmitter chemicals are released by
A) the dendritic membrane.
B) the presynaptic membrane.
C) axon hillocks.
D) cell bodies.
E) ducts on the smooth endoplasmic reticulum.

B

8) In a simple synapse, neurotransmitter chemicals are received by
A) the dendritic membrane.
B) the presynaptic membrane.
C) axon hillocks.
D) cell bodies.
E) ducts on the smooth endoplasmic reticulum.

A

12) The operation of the sodium-potassium "pump" moves
A) sodium and potassium ions into the cell.
B) sodium and potassium ions out of the cell.
C) sodium ions into the cell and potassium ions out of the cell.
D) sodium ions out of the cell and potassium ions into the cell.
E) sodium and potassium ions into the mitochondria.

D

31) Saltatory conduction is a term applied to
A) conduction of impulses across electrical synapses.
B) an action potential that skips the axon hillock in moving from the dendritic region to the axon terminal.
C) rapid movement of an action potential reverberating back and forth along a neuron.
D) jumping from one neuron to an adjacent neuron.
E) jumping from one node of Ranvier to the next in a myelinated neuron.

E

33) Neurotransmitters are released from axon terminals via
A) osmosis.
B) active transport.
C) diffusion.
D) transcytosis.
E) exocytosis.

E

36) One possible disadvantage to a nerve net is that it might conduct impulses in two directions from the point of the stimulus. Most of the synapses in vertebrates conduct information in only one direction
A) as a result of the nodes of Ranvier.
B) as a result of voltage-gated sodium channels found only in the vertebrate system.
C) because vertebrate nerve cells have dendrites.
D) because only the postsynaptic cells can bind and respond to neurotransmitters.
E) because the sodium-potassium pump moves ions in one direction.

D

40) The following steps refer to various stages in transmission at a chemical synapse:
1. Neurotransmitter binds with receptors associated with the postsynaptic membrane.
2. Calcium ions rush into neuron's cytoplasm.
3. An action potential depolarizes the membrane of the axon terminal.
4. The ligand-gated ion channels open.
5. The synaptic vesicles release neurotransmitter into the synaptic cleft.

Which sequence of events is correct?

A) 1 → 2 → 3 → 4 → 5
B) 2 → 3 → 5 → 4 → 1
C) 3 → 2 → 5 → 1 → 4
D) 4 → 3 → 1 → 2 → 5
E) 5 → 1 → 2 → 4 → 3

C

41) The activity of acetylcholine in a synapse is terminated by
A) its active transport across the presynaptic membrane.
B) its diffusion across the presynaptic membrane.
C) its active transport across the postsynaptic membrane.
D) its diffusion across the postsynaptic membrane.
E) its degradation by a hydrolytic enzyme on the postsynaptic membrane.

E

42) Adjacent neurons with direct (non-neurotransmitter) action potential transfer are said to have electrical synapses, based on the presence of
A) tight junctions at their point of contact.
B) gap junctions at their point of contact.
C) leaky junctions at their point of contact.
D) anchoring junctions at their point of contact.
E) desmosomes at their point of contact.

B

43) Ionotropic receptors are found at synapses operated via
A) ligand-gated ion channels.
B) second-messenger-gated ion channels.
C) electrical synapses.
D) inhibitory, but not excitatory, synapses.
E) excitatory, but not inhibitory, synapses.

A

46) Neurotransmitters categorized as inhibitory are expected to
A) act independently of their receptor proteins.
B) close potassium channels.
C) open sodium channels.
D) close chloride channels.
E) hyperpolarize the membrane.

E

47) When several EPSPs arrive at the axon hillock from different dendritic locations, depolarizing the postsynaptic cell to threshold for an action potential, this is an example of
A) temporal summation.
B) spatial summation.
C) tetanus.
D) the refractory state.
E) an action potential with an abnormally high peak of depolarization.

B

48) When several IPSPs arrive at the axon hillock rapidly in sequence from a single dendritic location, hyperpolarizing the postsynaptic cell more and more and thus preventing an action potential, this is an example of
A) temporal summation.
B) spatial summation.
C) tetanus.
D) the refractory state.
E) an action potential with an abnormally high peak of depolarization.

A

50) Receptors for neurotransmitters are of primary functional importance in assuring one-way synaptic transmission because they are mostly found on the
A) axonal membrane.
B) axon hillock.
C) dendritic membrane.
D) mitochondrial membrane.
E) presynaptic membrane.

C

51) Functionally, which cellular location is the neuron's "decision-making site" as to whether or not an action potential will be initiated?
A) axonal membranes
B) axon hillocks
C) dendritic membranes
D) mitochondrial membranes
E) presynaptic membranes

B

52) Neurotransmitters affect postsynaptic cells by
A) initiating signal transduction pathways in the cells.
B) causing molecular changes in the cells.
C) affecting ion-channel proteins.
D) altering the permeability of the cells.
E) All of these options are correct.

E

57) An amino acid that operates at inhibitory synapses in the brain is
A) acetylcholine.
B) epinephrine.
C) endorphin.
D) nitric oxide.
E) GABA.

E

66) Action potentials are normally carried in only one direction: from the axon hillock toward the axon terminals. If you experimentally depolarize the middle of the axon to threshold, using an electronic probe, then
A) no action potential will be initiated.
B) an action potential will be initiated and proceed only in the normal direction toward the axon terminal.
C) an action potential will be initiated and proceed only back toward the axon hillock.
D) two action potentials will be initiated, one going toward the axon terminal and one going back toward the hillock.
E) an action potential will be initiated, but it will die out before it reaches the axon terminal.

D

71) Temporal summation always involves
A) both inhibitory and excitatory inputs.
B) synapses at more than one site.
C) inputs that are not simultaneous.
D) electrical synapses.
E) multiple inputs at a single synapse.

E

2) The central nervous system is lacking in animals that have
A) a complete gut.
B) bilateral symmetry.
C) radial symmetry.
D) a closed circulatory system.
E) excitable membranes

B

18) The activation of the parasympathetic branch of the autonomic nervous system is associated with
A) resting and digesting.
B) release of epinephrine into the blood.
C) increased metabolic rate.
D) fight-or-flight responses.
E) intensive aerobic exercise.

A

22) The system that modulates excitation and inhibition of smooth and cardiac muscles of the digestive, cardiovascular, and excretory systems is the
A) central nervous system.
B) peripheral nervous system.
C) autonomic nervous system.
D) parasympathetic nervous system.
E) sympathetic nervous system.

C

26) Bottlenose dolphins breathe air but can sleep in the ocean because
A) they cease breathing while sleeping and remain underwater.
B) they sleep for only 30 minutes at a time, which is the maximum interval they can cease breathing.
C) they fill their swim bladder with air to keep their blowholes above the surface of the water while they sleep.
D) they move to shallow water to sleep, so they do not need to swim to keep their blowholes above the surface of the water.
E) they alternate which half of their brains is asleep and which half is awake.

E

27) The limbic system in the central nervous system sustains many vegetative functions in mammals and is closely associated with structures that process cues about
A) gustation.
B) olfaction.
C) vision.
D) audition.

B

34) The regulation of body temperature derives from the activity of the
A) cerebrum.
B) cerebellum.
C) thalamus.
D) hypothalamus.
E) medulla oblongata.

D

37) Which processes in animals are regulated by circadian rhythms?
A) sleep cycles
B) hormone release
C) sex drive
D) sleep cycles and hormone release only
E) sleep cycles, hormone release, and sex drive

E

51) Bipolar disorder is similar to schizophrenia in that researchers suspect that both include trouble with the neurotransmitter
A) dopamine.
B) acetylcholine.
C) norepinephrine.
D) nitric oxide.
E) ethanol.

A

52) Bipolar disorder differs from schizophrenia in that
A) schizophrenia results in hallucinations.
B) schizophrenia results in both manic and depressive states.
C) schizophrenia results in decreased dopamine.
D) bipolar disorder involves both genes and environment.
E) bipolar disorder increases biogenic amines.

A

63) The cerebral cortex plays a major role in all of the following except
A) short-term memory.
B) long-term memory.
C) circadian rhythm.
D) foot-tapping rhythm.
E) breath holding.

C

65) Injury localized to the hypothalamus would most likely disrupt
A) short-term memory.
B) coordination during locomotion.
C) executive functions, such as decision making.
D) sorting of sensory information.
E) regulation of body temperature.

E