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Flashcards in human body systems test Deck (233):
1

1) All hormones

A) are produced by endocrine glands.

B) are lipid-soluble molecules.

C) are carried to target cells in the blood.

D) are protein molecules.

E) elicit the same biological response from all of their target cells.

 

C) are carried to target cells in the blood.

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2) In a positive-feedback system where hormone A alters the amount of protein X

A) an increase in A always produces an increase in X.

B) an increase in X always produces a decrease in A.

C) a decrease in A always produces an increase in X.

D) a decrease in X always causes a decrease in A.

E) it is impossible to predict how A and X affect each other.

 

A) an increase in A always produces an increase in X.

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3) Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of

A) an autocrine signal.

B) a paracrine signal.

C) an endocrine signal.

D) both an autocrine signal and a paracrine signal.

E) an autocrine signal, a paracrine signal, and an endocrine signal.

 

E) an autocrine signal, a paracrine signal, and an endocrine signal.

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4) Which category of signal exerts its effects on target cells by binding to membrane-bound receptor proteins?

A) neurohormones

B) estrogens

C) androgens

D) vitamin D

E) neurohormones, estrogens, androgens, and vitamin D

 

A) neurohormones

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5) A paracrine signal that relaxes smooth muscle cells is

A) nitric oxide.

B) vitamin D.

C) testosterone.

D) cortisol.

E) antidiuretic hormone.

 

A) nitric oxide.

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6) Prostaglandins are local regulators whose chemical structure is derived from

A) oligosaccharides.

B) fatty acids.

C) steroids.

D) amino acids.

E) nitric oxide.

 

B) fatty acids.

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8) Aspirin and ibuprofen both

A) inhibit the synthesis of prostaglandins.

B) inhibit the release of nitric oxide, a potent vasodilator.

C) activate the paracrine signaling pathways that form blood clots.

D) stimulate the release of oxytocin.

E) stimulate vasoconstriction in the kidneys.

 

A) inhibit the synthesis of prostaglandins.

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9) A cell with membrane-bound proteins that selectively bind a specific hormone is called that hormone's

A) secretory cell.

B) plasma cell.

C) endocrine cell.

D) target cell.

E) regulatory cell.

 

D) target cell.

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10) The reason that the steroid hormone aldosterone affects only a small number of cells in the body is that

A) only its target cells get exposed to aldosterone.

B) only its target cells contain aldosterone receptors.

C) it is unable to enter nontarget cells.

D) nontarget cells destroy aldosterone before it can produce any effect.

E) nontarget cells convert aldosterone to a hormone to which they do respond.

 

B) only its target cells contain aldosterone receptors.

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11) Different body cells can respond differently to the same peptide hormones because

A) different target cells have different sets of genes.

B) each cell converts that hormone to a different metabolite.

C) a target cell's response is determined by the components of its signal transduction pathways.

D) the circulatory system regulates responses to hormones by routing the hormones to specific targets.

E) the hormone is chemically altered in different ways as it travels through the circulatory system.

 

C) a target cell's response is determined by the components of its signal transduction pathways.

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12) Insect hormones and their receptors

A) act independently of each other.

B) are a focus in pest-control research.

C) utilize cell-surface receptors only.

D) are active independently of environmental cues.

E) are not relevant to the study of steroid hormones.

 

B) are a focus in pest-control research.

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14) A chemical signal operating in a paracrine manner is one that

A) is active at a neuronal synapse.

B) affects only the cells that synthesize the paracrine signal.

C) requires transport in the blood before it can act on its target cells.

D) evokes responses from all parts of the vascular system.

E) must move through the air before it reaches its target cells.

 

A) is active at a neuronal synapse.

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15) Hormone X activates the cAMP second messenger system in its target cells. The greatest response by a cell would come from

A) applying a molecule of hormone X to the extracellular fluid surrounding the cell.

B) injecting a molecule of hormone X into the cytoplasm of the cell.

C) applying a molecule of cAMP to the extracellular fluid surrounding the cell.

D) injecting a molecule of cAMP into the cytoplasm of the cell.

E) injecting a molecule of activated, cAMP-dependent protein kinase into the cytoplasm of the cell.

 

A) applying a molecule of hormone X to the extracellular fluid surrounding the cell.

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16) When a steroid hormone and a peptide hormone exert similar effects on a population of target cells, then

A) the steroid and peptide hormones must use the same biochemical mechanisms.

B) the steroid and peptide hormones must bind to the same receptor protein.

C) the steroid hormones affect the synthesis of effector proteins, whereas peptide hormones activate effector proteins already present in the cell.

D) the steroid hormones affect the activity of certain proteins within the cell, whereas peptide hormones directly affect the processing of mRNA.

E) the steroid hormones affect only the release of proteins from the target cell, whereas peptide hormones affect only the synthesis of proteins that remain in the target cell.

 

C) the steroid hormones affect the synthesis of effector proteins, whereas peptide hormones activate effector proteins already present in the cell.

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17) For hormones that homeostatically regulate cellular functions,

A) negative feedback typically regulates hormone secretion.

B) the circulating level of a hormone is held constant through a series of positive feedback loops.

C) both lipid-soluble hormones and water-soluble hormones bind to intracellular protein receptors.

D) endocrine organs release their contents into the bloodstream via specialized ducts.

E) it is impossible to also have neural regulation of that system.

 

A) negative feedback typically regulates hormone secretion.

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18) Nitric oxide and epinephrine

A) both function as neurotransmitters.

B) both function as steroid hormones.

C) are both involved in the "fight-or-flight" response.

D) bind the same receptors.

E) both cause a reduction in the blood levels of glucose.

 

A) both function as neurotransmitters.

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19) Suppose that substance X is secreted by one cell, travels via interstitial fluid to a neighboring cell, and produces an effect on that cell. All of the following terms could describe this substance except

A) paracrine signal.

B) neurotransmitter.

C) prostaglandin.

D) pheromone.

E) growth factor.

 

D) pheromone.

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20) Hormones that promote homeostasis

A) are not found as members of antagonistic signaling mechanisms.

B) travel to target cells without passage in the plasma.

C) utilize receptors that bind any hormone.

D) initiate signal transduction in the target cell without binding to receptors.

E) usually operate as part of a negative feedback system.

 

E) usually operate as part of a negative feedback system.

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21) During mammalian labor and delivery, the contraction of uterine muscles is enhanced by oxytocin. This is an example of

A) a negative feedback system.

B) a hormone that acts in an antagonistic way with another hormone.

C) a hormone that is involved in a positive feedback loop.

D) signal transduction immediately changing gene expression in its target cells.

E) the key role of the anterior pituitary gland in regulating uterine contraction.

 

C) a hormone that is involved in a positive feedback loop.

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22) During short-term starvation, most available fuel molecules are catabolized to provide energy for metabolism rather than being used as building blocks for growth and repair, a trade-off that is hormonally regulated by

A) acetylcholine.

B) glucagon.

C) oxytocin.

D) antidiuretic hormone.

E) insulin.

 

B) glucagon.

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24) The interrelationships between the endocrine and the nervous systems are especially apparent in

A) a neuron in the spinal cord.

B) a steroid-producing cell in the adrenal cortex.

C) a neurosecretory cell in the hypothalamus.

D) a brain cell in the cerebral cortex.

E) a cell in the pancreas that produces digestive enzymes.

 

C) a neurosecretory cell in the hypothalamus.

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25) The hypothalamus modulates hormone secretion by the anterior pituitary by means of

A) peptide hormones.

B) steroid hormones.

C) electrical synapses.

D) neurotransmitters.

E) paracrine signals.

 

A) peptide hormones.

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28) The hypothalamus

A) functions only as an endocrine target, by having lots of receptors on its cells.

B) functions only in neuronal transmission.

C) does not have any hormone receptors on its cells.

D) secretes tropic hormones that act directly on the gonads.

E) includes neurosecretory cells that terminate in the posterior pituitary.

 

E) includes neurosecretory cells that terminate in the posterior pituitary.

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29) Prolactin stimulates mammary gland growth and development in mammals and regulates salt and water balance in freshwater fish. Many scientists think that this wide range of functions indicates that prolactin

A) is a nonspecific hormone.

B) has a unique mechanism for eliciting its effects.

C) is an evolutionarily conserved hormone.

D) is derived from two separate sources.

E) interacts with many different receptor molecules.

 

C) is an evolutionarily conserved hormone.

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44) Analysis of a blood sample from a fasting individual who had not eaten for 24 hours would be expected to reveal high levels of

A) insulin.

B) glucagon.

C) secretin.

D) gastrin.

E) glucose.

 

B) glucagon.

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45) When the beta cells of the pancreas release insulin into the blood,

A) the blood glucose levels rise to a set point and stimulate glucagon release.

B) the skeletal muscles and the adipose cells take up glucose at a faster rate.

C) the liver catabolizes glycogen.

D) the alpha cells of the pancreas release glucose into the blood.

E) the kidneys begin gluconeogenesis.

 

B) the skeletal muscles and the adipose cells take up glucose at a faster rate.

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50) During a stressful interval

A) TSH stimulates the adrenal cortex and medulla to secrete acetylcholine.

B) the alpha cells of islets secrete insulin and simultaneously the beta cells of the islets secrete glucagon.

C) ACTH stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla.

D) the posterior pituitary gland secretes more growth hormones.

E) the calcium levels in the blood are increased due to actions of two antagonistic hormones, epinephrine and norepinephrine.

 

C) ACTH stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla.

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63) In an experiment, rats' ovaries were removed immediately after impregnation and then the rats were divided into two groups. Treatments and results are summarized in the table. The results most likely occurred because progesterone exerts an effect on the

A) general health of the rat.

B) size of the fetus.

C) metabolism of the uterus.

D) gestation period of rats.

E) number of eggs fertilized.

 

Q image thumb

C) metabolism of the uterus.

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64) A fantasy movie features a caterpillar that never matures into an adult, but simply gets larger and larger with each molt. It might be possible that the caterpillar did not mature into an adult because of

A) a lack of ecdysone.

B) a lack of juvenile hormone.

C) a decreased level of ecdysone.

D) an increased level of juvenile hormone.

E) a lack of melatonin.

 

D) an increased level of juvenile hormone.

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65) Which of the following is not an accurate statement?

A) Hormones are chemical messengers that travel to target cells through the circulatory system.

B) Hormones often regulate homeostasis through antagonistic functions.

C) Hormones of the same chemical class usually have the same function.

D) Hormones are secreted by specialized cells usually located in endocrine glands.

E) Hormones are often regulated through feedback loops.

 

 

 

C) Hormones of the same chemical class usually have the same function.

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67) Growth factors are local regulators that

A) are produced by the anterior pituitary.

B) are modified fatty acids that stimulate bone and cartilage growth.

C) are found on the surface of cancer cells and stimulate abnormal cell division.

D) bind to cell-surface receptors and stimulate growth and development of target cells.

E) convey messages between nerve cells.

 

D) bind to cell-surface receptors and stimulate growth and development of target cells.

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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) bilateral symmetry.

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3) Cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in

A) Hydra.

B) cnidarians.

C) Planaria.

D) sea stars.

E) invertebrate animals with radial symmetry.

 

C) Planaria.

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4) An organism that lacks integration centers

A) cannot receive stimuli.

B) will not have a nervous system.

C) will not be able to interpret stimuli.

D) can be expected to lack myelinated neurons.

 

C) will not be able to interpret stimuli.

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5) In the human knee-jerk reflex, as the calf is raised from the vertical toward the horizontal, the muscles of the quadriceps (flexors on the ventral side of the thighs) and the muscles of the hamstring (extensors on the dorsal side of the thighs) are

A) both excited and contracting.

B) both inhibited and relaxed.

C) excited and inhibited, respectively.

D) inhibited and excited, respectively.

 

C) excited and inhibited, respectively.

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6) The stretch receptors of the sensory neurons in the human knee-jerk reflex are located in the

A) gastrocnemius muscle, in the calf.

B) cartilage of the knee.

C) quadriceps, the flexor muscles on the ventral side of the thighs.

D) hamstring, the extensor muscles on the dorsal side of the thighs.

E) brain, the sensorimotor relay.

 

C) quadriceps, the flexor muscles on the ventral side of the thighs.

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7) Choose the correct match of glial cell type and function.

A) astrocytes metabolize neurotransmitters and modulate synaptic effectiveness

B) oligodendrocytes produce the myelin sheaths of myelinated neurons in the peripheral nervous system

C) microglia produce the myelin sheaths of myelinated neurons in the central nervous system

D) radial gliathe source of immunoprotection against pathogens.

E) Schwann cells provide nutritional support to non-myelinated neurons

 

A) astrocytes metabolize neurotransmitters and modulate synaptic effectiveness

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8) The cerebrospinal fluid is

A) a filtrate of the blood.

B) a secretion of glial cells.

C) a secretion of interneurons.

D) cytosol secreted from ependymal cells.

E) secreted by the hypothalamus.

 

A) a filtrate of the blood.

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9) The human knee-jerk reflex requires an intact

A) spinal cord.

B) hypothalamus.

C) corpus callosum.

D) cerebellum.

E) medulla.

 

A) spinal cord.

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10) The blood-brain barrier

A) is formed by tight junctions.

B) is formed by oligodendrocytes.

C) tightly regulates the intracellular environment of the CNS.

D) uses chemical signals to communicate with the spinal cord.

E) provides support to the brain tissue.

 

A) is formed by tight junctions.

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11) Myelinated neurons are especially abundant in the

A) gray matter of the brain and the white matter of the spinal cord.

B) white matter of the brain and the gray matter of the spinal cord.

C) gray matter of the brain and the gray matter of the spinal cord.

D) white matter in the brain and the white matter in the spinal cord.

E) all areas of the brain and spinal cord.

 

D) white matter in the brain and the white matter in the spinal cord.

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13) Cerebrospinal fluid can be described as all of the following except

A) functioning in transport of nutrients and hormones through the brain.

B) a product of the filtration of blood in the brain.

C) formed from layers of connective tissue.

D) functioning to cushion the brain.

E) filling cavities in the brain called ventricles.

 

C) formed from layers of connective tissue.

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16) Exercise and emergency reactions include

A) increased activity in all parts of the peripheral nervous system.

B) increased activity in the sympathetic, and decreased activity in the parasympathetic branches.

C) decreased activity in the sympathetic, and increased activity in the parasympathetic branches.

D) increased activity in the enteric nervous system.

E) reduced heart rate and blood pressure.

 

B) increased activity in the sympathetic, and decreased activity in the parasympathetic branches.

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17) Increased activity in the sympathetic nervous system leads to

A) decreased heart rate.

B) increased secretion by the pancreas.

C) increased secretion by the gallbladder.

D) increased contraction of the stomach.

E) relaxation of the airways in the lungs.

 

E) relaxation of the airways in the lungs.

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19) In a cephalized invertebrate, the system that transmits "efferent" impulses from the anterior ganglion to distal segments is the

A) central nervous system.

B) peripheral nervous system.

C) autonomic nervous system.

D) parasympathetic nervous system.

E) sympathetic nervous system.

 

B) peripheral nervous system.

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20) Afferent neuronal systems include the

A) sensory systems.

B) peripheral nervous system.

C) autonomic nervous system.

D) parasympathetic nervous system.

E) sympathetic nervous system.

 

A) sensory systems.

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21) Cranial nerves originate in the brain and are thus part of the

A) central nervous system.

B) peripheral nervous system.

C) autonomic nervous system.

D) parasympathetic nervous system.

E) sympathetic nervous system.

 

A) central nervous system.

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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) autonomic nervous system.

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25) The endogenous nature of biological rhythms is based on the observations that animals isolated from light and dark cues

A) continue to have cycles of exactly 24 hours' duration.

B) continue to have cycles of approximately 24 hours' duration; some more rapid, some slower.

C) synchronize activity with whatever lighting cycle is imposed on them.

D) cease having any rhythms.

E) are independent of any genetic determinants.

 

B) continue to have cycles of approximately 24 hours' duration; some more rapid, some slower.

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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) they alternate which half of their brains is asleep and which half is awake.

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40) In mammals, advanced cognition is usually correlated with a large and very convoluted neocortex, but birds are capable of sophisticated cognition because they have

A) a more advanced cerebellum.

B) a cerebellum with several flat layers.

C) a pallium with neurons clustered into nuclei.

D) microvilli to increase the brain's surface area.

 

C) a pallium with neurons clustered into nuclei.

52

47) Failure of an embryonic neuron to establish a synaptic connection to another cell

A) converts that neuron to an ependymal cell.

B) causes the neuron to migrate to another part of the brain.

C) converts that neuron to a glial cell.

D) leads to Alzheimer's disease.

E) results in the apoptosis of that neuron.

 

E) results in the apoptosis of that neuron.

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49) Learning a new language during adulthood alters activity in the brain's language processing locations by

A) altering synaptic effectiveness in these locations.

B) increasing the rate of mitosis in these locations.

C) inhibiting synapses that work in the previously learned language.

D) causing established neurons to produce different neurotransmitter molecules.

E) forming electrical synapses between cells.

 

A) altering synaptic effectiveness in these locations.

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58) Imagine you are resting comfortably on a sofa after dinner. This could be described as a state with

A) increased activity in the sympathetic, parasympathetic, and enteric nervous systems.

B) decreased activity in the sympathetic, parasympathetic, and enteric nervous systems.

C) decreased activity in the sympathetic nervous system, and increased activity in the parasympathetic and enteric nervous systems.

D) increased activity in the sympathetic nervous system, and decreased activity in the parasympathetic and enteric nervous systems.

E) increased activity in the sympathetic nervous system, decreased activity in the parasympathetic nervous system, and increased activity in the enteric nervous system.

 

C) decreased activity in the sympathetic nervous system, and increased activity in the parasympathetic and enteric nervous systems.

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1) A necropsy (postmortem analysis) of a marine sea star that died after it was mistakenly placed in fresh water would likely show that it died because

A) it was stressed and needed more time to acclimate to the new conditions.

B) it was so hyperosmotic to the fresh water that it could not osmoregulate.

C) the sea star's kidneys could not handle the change in ionic content presented by the fresh water.

D) its contractile vacuoles ruptured.

E) its cells dehydrated and lost the ability to metabolize.

 

B) it was so hyperosmotic to the fresh water that it could not osmoregulate.

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2) Organisms categorized as osmoconformers are most likely

A) found in freshwater lakes and streams.

B) marine.

C) amphibious.

D) found in arid terrestrial environments.

E) found in terrestrial environments with adequate moisture.

 

B) marine.

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3) The body fluids of an osmoconformer would be ________ with its ________ environment.

A) hyperosmotic; freshwater

B) isotonic; freshwater

C) hyperosmotic; saltwater

D) isoosmotic; saltwater

E) hypoosmotic; saltwater

 

D) isoosmotic; saltwater

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4) Compared to the seawater around them, most marine invertebrates are

A) hyperosmotic.

B) hypoosmotic.

C) isoosmotic.

D) hyperosmotic and isoosmotic.

E) hypoosmotic and isoosmotic.

 

C) isoosmotic.

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5) The fluid with the highest osmolarity is

A) distilled water.

B) plasma in birds.

C) plasma in mammals.

D) seawater in a tidal pool.

E) estuarine water.

 

D) seawater in a tidal pool.

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6) Birds that live in marine environments and thus lack access to fresh drinking water

A) osmoregulate without using a transport epithelium for this purpose.

B) drink seawater and secrete excess ions through their kidneys only.

C) drink seawater and secrete excess ions mainly through their nasal salt glands.

D) have plasma that is isoosmotic to ocean water.

E) obtain water by eating only osmoregulating prey.

 

C) drink seawater and secrete excess ions mainly through their nasal salt glands.

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7) Osmoconforming sharks take in water, as needed,

A) by migrating to freshwater rivers to drink fresh water.

B) via osmosis, as their body cells are slightly hyperosmotic to seawater.

C) via active transport of water across the cells on their gills.

D) by water diffusion from seawater, which is hyperosmotic to the fluids in their cells.

E) by selective transport of water molecules across the wall of the gut.

 

B) via osmosis, as their body cells are slightly hyperosmotic to seawater.

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8) A human who has no access to fresh water but is forced to drink seawater instead

A) will thrive under such conditions, as long as he has lived at the ocean most of his life.

B) will excrete more water molecules than taken in, because of the high load of ion ingestion.

C) will develop structural changes in the kidneys to accommodate the salt overload.

D) will find that drinking saltwater satiates his thirst.

E) will risk becoming overhydrated within 12 hours.

 

B) will excrete more water molecules than taken in, because of the high load of ion ingestion.

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9) Many marine and freshwater bony fish achieve osmoregulation via

A) loss of water through the gills.

B) gain of salt through the gills.

C) loss of water in the urine.

D) no drinking of water.

E) gain of water through food.

 

E) gain of water through food.

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10) Unlike most bony fishes, sharks maintain body fluids that are isoosmotic to seawater, so they are considered by many to be osmoconformers. Nonetheless, these sharks osmoregulate at least partially by

A) using their gills and kidneys to rid themselves of sea salts.

B) monitoring dehydration at the cellular level with special gated aquaporins.

C) tolerating high urea concentrations that balance internal salt concentrations to seawater osmolarity.

D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells.

E) possessing a special adaptation that allows their cells to operate at an extraordinarily high salt concentration.

 

C) tolerating high urea concentrations that balance internal salt concentrations to seawater osmolarity.

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11) The necropsy (postmortem analysis) of a freshwater fish that died after being placed accidentally in saltwater would likely show that

A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure.

B) high amounts of salt had diffused into the fish's cells, causing them to swell and lyse.

C) the kidneys were not able to keep up with the water removal necessary in this hyperosmotic environment, creating an irrevocable loss of homeostasis.

D) the gills became encrusted with salt, resulting in inadequate gas exchange and a resulting asphyxiation.

E) brain cells lysed as a result of increased osmotic pressure in this hyperosmotic environment, leading to death by loss of autonomic function.

 

A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure.

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12) Urea is produced in the

A) liver from NH3 and CO2.

B) liver from glycogen.

C) kidneys from glucose.

D) kidneys from glycerol and fatty acids.

E) bladder from uric acid and H2O.

 

A) liver from NH3 and CO2.

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13) Urea is

A) insoluble in water.

B) more toxic to human cells than ammonia.

C) the primary nitrogenous waste product of humans.

D) the primary nitrogenous waste product of most birds.

E) the primary nitrogenous waste product of most aquatic invertebrates.

 

C) the primary nitrogenous waste product of humans.

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14) Which nitrogenous waste has the greatest number of nitrogen atoms?

A) ammonia

B) ammonium ions

C) urea

D) uric acid

 

D) uric acid

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15) Ammonia is likely to be the primary nitrogenous waste in living conditions that include

A) lots of fresh water flowing across the gills of a fish.

B) lots of seawater, such as a bird living in a marine environment.

C) lots of seawater, such as a marine mammal (e.g., a polar bear).

D) a terrestrial environment, such as that supporting crickets.

E) a moist system of burrows, such as those of naked mole rats.

 

A) lots of fresh water flowing across the gills of a fish.

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16) Among vertebrate animals, urea

A) is made in the kidneys and immediately excreted.

B) is added to the air in the lungs to be exhaled, along with carbon dioxide.

C) is made in the liver by combining two ammonia molecules with one carbon dioxide.

D) is made in the pancreas and added to the intestinal contents, along with bile salts, for excretion.

E) is rarely the nitrogenous waste of choice.

 

C) is made in the liver by combining two ammonia molecules with one carbon dioxide.

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17) The nitrogenous waste that requires the most energy to produce is

A) ammonia.

B) ammonium.

C) urea.

D) uric acid.

 

D) uric acid.

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18) Excessive formation of uric acid crystals in humans leads to

A) a condition called diabetes, where excessive urine formation occurs.

B) a condition of insatiable thirst and excessive urine formation.

C) gout, a painful inflammatory disease that primarily affects the joints.

D) the absence of urea in the urine.

E) osteoarthritis, an inevitable consequence of aging.

 

C) gout, a painful inflammatory disease that primarily affects the joints.

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19) Ammonia

A) is soluble in water.

B) can be stored in the body as a precipitate.

C) has low toxicity relative to urea.

D) is metabolically more expensive to synthesize than urea.

E) is the major nitrogenous waste excreted by insects.

 

A) is soluble in water.

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20) The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that

A) urea can be exchanged for Na+.

B) urea is less toxic than ammonia.

C) urea requires more water for excretion than ammonia.

D) urea does not affect the osmolar gradient.

E) less nitrogen is removed from the body.

 

B) urea is less toxic than ammonia.

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23) In animals, nitrogenous wastes are produced mostly from the catabolism of

A) starch and cellulose.

B) triglycerides and steroids.

C) proteins and nucleic acids.

D) phospholipids and glycolipids.

E) fatty acids and glycerol.

 

C) proteins and nucleic acids.

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24) Birds secrete uric acid as their nitrogenous waste because uric acid

A) is readily soluble in water.

B) is metabolically less expensive to synthesize than other excretory products.

C) requires little water for nitrogenous waste disposal, thus reducing body mass.

D) excretion allows birds to live in desert environments.

 

C) requires little water for nitrogenous waste disposal, thus reducing body mass.

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25) Among the following choices, the most concentrated urine is excreted by

A) frogs.

B) kangaroo rats.

C) humans.

D) desert tortoises.

E) birds.

 

B) kangaroo rats.

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26) Materials are returned to the blood from the filtrate by which of the following processes?

A) filtration

B) ultrafiltration

C) selective reabsorption

D) secretion

E) active transport

 

C) selective reabsorption

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31) The osmoregulatory process called secretion refers to the

A) formation of filtrate at an excretory structure.

B) reabsorption of nutrients from a filtrate.

C) selective elimination of excess ions and toxins from body fluids.

D) formation of an osmotic gradient along an excretory structure.

E) expulsion of urine from the body.

 

C) selective elimination of excess ions and toxins from body fluids.

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34) Which of the following pairs of organisms excrete nitrogenous wastes in the form of uric acid?

A) mice and birds

B) insects and birds

C) lions and horses

D) humans and frogs

E) fish and turtles

 

B) insects and birds

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35) Choose a pair that correctly associates the mechanism for osmoregulation or nitrogen removal with the appropriate animal.

A) metanephridium flatworm

B) Malpighian tubule frog

C) kidney insect

D) flame bulb snake

E) direct cellular exchange marine invertebrate

 

E) direct cellular exchange marine invertebrate

82

36) An excretory system that is partly based on the filtration of fluid under high hydrostatic pressure is the

A) flame bulb system of flatworms.

B) protonephridia of rotifers.

C) metanephridia of earthworms.

D) Malpighian tubules of insects.

E) kidneys of vertebrates.

 

E) kidneys of vertebrates.

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37) The transfer of fluid from the glomerulus to Bowman's capsule

A) results from active transport.

B) transfers large molecules as easily as small ones.

C) is very selective as to which subprotein-sized molecules are transferred.

D) is mainly a consequence of blood pressure in the capillaries of the glomerulus.

E) usually includes the transfer of red blood cells into Bowman's capsule.

 

D) is mainly a consequence of blood pressure in the capillaries of the glomerulus.

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43) Human urine is usually more acidic than most other body fluids because

A) hydrogen ions are actively moved into the filtrate.

B) the sodium transporter exchanges one hydrogen ion for each sodium ion.

C) excreted plasma proteins are nearly all acidic ions.

D) excreted amino acids are in abundance.

E) potassium and sodium exchange generates lots of acidity.

 

A) hydrogen ions are actively moved into the filtrate.

85

44) The osmolarity of human urine

A) can be four times as great as normal osmolarity of human plasma.

B) is always exactly equal to plasma osmolarity.

C) is always less than plasma osmolarity.

D) is always greater than plasma osmolarity.

E) is determined primarily by the concentration of glucose.

 

A) can be four times as great as normal osmolarity of human plasma.

86

45) A primary reason that the kidneys have one of the highest metabolic rates of all body organs is that

A) it stores the body's excess fats.

B) it has membranes of varying permeability to water.

C) it operates an extensive set of active-transport ion pumps.

D) it is the body's only means of shedding excess nutrients.

E) it has an abundance of myogenic smooth muscle.

 

C) it operates an extensive set of active-transport ion pumps.

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46) Low selectivity of solute movement is a characteristic of

A) salt pumping to control osmolarity.

B) H+ pumping to control pH.

C) reabsorption mechanisms along the proximal tubule.

D) filtration from the glomerular capillaries.

E) secretion along the distal tubule.

 

D) filtration from the glomerular capillaries.

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47) If ATP production in a human kidney was suddenly halted, urine production would

A) come to a complete halt.

B) decrease, and the urine would be hypoosmotic compared to plasma.

C) increase, and the urine would be isoosmotic compared to plasma.

D) increase, and the urine would be hyperosmotic compared to plasma.

E) decrease, and the urine would be isoosmotic compared to plasma.

 

C) increase, and the urine would be isoosmotic compared to plasma.

89

49) Processing of filtrate in the proximal and distal tubules

A) achieves the sorting of plasma proteins according to size.

B) achieves the conversion of toxic ammonia to less toxic urea.

C) maintains homeostasis of pH in body fluids.

D) regulates the speed of blood flow through the nephrons.

E) reabsorbs urea to maintain osmotic balance.

 

C) maintains homeostasis of pH in body fluids.

90

50) In humans, the transport epithelial cells in the ascending loop of Henle

A) are the largest epithelial cells in the body.

B) are not in contact with interstitial fluid.

C) have plasma membranes of low permeability to water.

D) have 50% of their cell mass made of smooth endoplasmic reticulum.

E) are not affected by high levels of nitrogenous wastes.

 

C) have plasma membranes of low permeability to water.

91

54) Increased ADH secretion is likely after

A) drinking lots of pure water.

B) sweating-induced dehydration increases plasma osmolarity.

C) ingestion of ethanol (drinking alcoholic drinks).

D) eating a small sugary snack.

E) blood pressure is abnormally high.

 

B) sweating-induced dehydration increases plasma osmolarity.

92

56) After drinking alcoholic beverages, increased urine excretion is the result of

A) increased aldosterone production.

B) increased blood pressure.

C) inhibited secretion of antidiuretic hormone (ADH).

D) increased reabsorption of water in the proximal tubule.

E) the osmoregulator cells of the brain increasing their activity.

 

C) inhibited secretion of antidiuretic hormone (ADH).

93

57) Osmoregulatory adjustment via the renin-angiotensin-aldosterone system can be triggered by

A) sleeping for one hour.

B) severe sweating on a hot day.

C) eating a bag of potato chips.

D) eating a pizza with olives and pepperoni.

E) drinking several glasses of water.

 

B) severe sweating on a hot day.

94

58) Antidiuretic hormone (ADH) functions at the cellular level by

A) stimulating the reabsorption of glucose through channel proteins.

B) triggering the synthesis of an enzyme that makes the phospholipid bilayer more permeable to water.

C) causing membranes to include more phospholipids that have unsaturated fatty acids.

D) causing an increase in the number of aquaporin molecules of collecting duct cells.

E) decreasing the speed at which filtrate flows through the nephron, leading to increased reabsorption of water.

 

D) causing an increase in the number of aquaporin molecules of collecting duct cells.

95

59) ADH and RAAS work together in maintaining osmoregulatory homeostasis through which of the following ways?

A) ADH regulates the osmolarity of the blood and RAAS regulates the volume of the blood.

B) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na+ reabsorption.

C) ADH and RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and RAAS causes increased excretion of water when it is in excess in body fluids.

D) both stimulate the adrenal gland to secrete aldosterone, which increases both blood volume and pressure via its receptors in the urinary bladder.

E) by combining at the receptor sites of proximal tubule cells, where reabsorption of essential nutrients takes place.

 

B) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na+ reabsorption.

96

60) Which of the following is excreted readily by aquatic animals because of its high solubility in the respiratory medium?

A) A

B) B

C) C

D) D

E) E

 

Q image thumb

A) A

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61) Which of the following is synthesized by mammals, most amphibians, sharks, and some bony fishes, and has lower toxicity than its nitrogenous substrate?

A) A

B) B

C) C

D) D

E) E

 

Q image thumb

B) B

98

62) Which of the following is excreted as a paste by land snails, insects, birds, and many reptiles, because of its solubility and toxicity properties?

A) A

B) B

C) C

D) D

E) E

 

Q image thumb

C) C

99

63) In a laboratory experiment with three groups of students, one group drinks pure water, a second group drinks an equal amount of beer, and a third group drinks an equal amount of concentrated salt solution, all during the same time period. Their urine production is monitored for several hours. Which groups are expected to have the greatest and least amounts of urine, respectively?

A) Beer drinkers have the most; salt solution drinkers have the least.

B) Salt solution drinkers have the most; water drinkers have the least.

C) Water drinkers have the most; beer drinkers have the least.

D) Beer drinkers have the most; water drinkers have the least.

E) There will be no significant difference between these groups.

 

A) Beer drinkers have the most; salt solution drinkers have the least.

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64) Unlike an earthworm's metanephridia, a mammalian nephron

A) is intimately associated with a capillary network.

B) forms urine by changing fluid composition inside a tubule.

C) functions in both osmoregulation and excretion.

D) receives filtrate from blood instead of coelomic fluid.

E) has a transport epithelium.

 

D) receives filtrate from blood instead of coelomic fluid.

101

65) Which process in the nephron is least selective?

A) filtration

B) reabsorption

C) active transport

D) secretion

E) salt pumping by the loop of Henle

 

A) filtration

102

66) Which of the following animals generally has the lowest volume of urine production?

A) a vampire bat

B) a salmon in freshwater

C) a marine bony fish

D) a freshwater bony fish

E) a shark inhabiting freshwater Lake Nicaragua

 

C) a marine bony fish

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67) The high osmolarity of the renal medulla is maintained by all of the following except

A) diffusion of salt from the thin segment of the ascending limb of the loop of Henle.

B) active transport of salt from the upper region of the ascending limb.

C) the spatial arrangement of juxtamedullary nephrons.

D) diffusion of urea from the collecting duct.

E) diffusion of salt from the descending limb of the loop of Henle.

 

E) diffusion of salt from the descending limb of the loop of Henle.

104

68) Natural selection should favor the highest proportion of juxtamedullary nephrons in which of the following species?

A) a river otter

B) a mouse species living in a tropical rain forest

C) a mouse species living in a temperate broadleaf forest

D) a mouse species living in a desert

E) a beaver

 

D) a mouse species living in a desert

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69) African lungfish, which are often found in small stagnant pools of fresh water, produce urea as a nitrogenous waste. What is the advantage of this adaptation?

A) Urea takes less energy to synthesize than ammonia.

B) Small stagnant pools do not provide enough water to dilute the toxic ammonia.

C) The highly toxic urea makes the pool uninhabitable to potential competitors.

D) Urea forms an insoluble precipitate.

E) Urea makes lungfish tissue hypoosmotic to the pool.

 

B) Small stagnant pools do not provide enough water to dilute the toxic ammonia.

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1) A simple nervous system

A) must include chemical senses, mechanoreception, and vision.

B) includes a minimum of 12 effector neurons.

C) has information flow in only one direction: toward an integrating center.

D) has information flow in only one direction: away from an integrating center.

E) includes sensory information, an integrating center, and effectors.

 

E) includes sensory information, an integrating center, and effectors.

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5) The somatic nervous system can alter the activities of its targets, the skeletal muscle fibers, because

A) it is electrically coupled by gap junctions to the muscles.

B) its signals bind to receptor proteins on the muscles.

C) its signals reach the muscles via the blood.

D) its light pulses activate contraction in the muscles.

E) it is connected to the internal neural network of the muscles.

 

B) its signals bind to receptor proteins on the muscles.

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10) For a neuron with an initial membrane potential at -70 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in

A) the depolarization of the neuron.

B) the hyperpolarization of the neuron.

C) the replacement of potassium ions with sodium ions.

D) the replacement of potassium ions with calcium ions.

E) the neuron switching on its sodium-potassium pump to restore the initial conditions.

 

B) the hyperpolarization of the neuron.

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11) Although the membrane of a "resting" neuron is highly permeable to potassium ions, its membrane potential does not exactly match the equilibrium potential for potassium because the neuronal membrane is also

A) fully permeable to sodium ions.

B) slightly permeable to sodium ions.

C) fully permeable to calcium ions.

D) impermeable to sodium ions.

E) highly permeable to chloride ions.

 

B) slightly permeable to sodium ions.

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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) sodium ions out of the cell and potassium ions into the cell.

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13) A cation that is more abundant as a solute in the cytosol of a neuron than it is in the interstitial fluid outside the neuron is

A) HCO3-.

B) Cl-.

C) Ca++.

D) Na+.

E) K+.

 

E) K+.

112

15) ATP hydrolysis directly powers the movement of

A) K+ out of cells.

B) Na+ out of cells.

C) Na+ into cells.

D) Ca++ into cells.

E) Cl- into cells.

 

B) Na+ out of cells.

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16) Two fundamental concepts about the ion channels of a "resting" neuron are that the channels

A) are always open, but the concentration gradients of ions frequently change.

B) are always closed, but ions move closer to the channels during excitation.

C) open and close depending on stimuli, and are specific as to which ion can traverse them.

D) open and close depending on chemical messengers, and are nonspecific as to which ion can traverse them.

E) open in response to stimuli, and then close simultaneously, in unison.

 

C) open and close depending on stimuli, and are specific as to which ion can traverse them.

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17) Opening all of the sodium channels, with all other ion channels closedwhich is an admittedly artificial  settingon an otherwise typical neuron should move its membrane potential to

A) -90 mV.

B) -70 mV.

C) 0 mV.

D) +30 mV.

E) +62 mV.

 

E) +62 mV.

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18) A graded hyperpolarization of a membrane can be induced by

A) increasing its membrane's permeability to Na+.

B) decreasing its membrane's permeability to H+.

C) decreasing its membrane's permeability to Cl-.

D) increasing its membrane's permeability to Ca++.

E) increasing its membrane's permeability to K+.

 

E) increasing its membrane's permeability to K+.

116

20) The "selectivity" of a particular ion channel refers to its

A) permitting passage by positive but not negative ions.

B) permitting passage by negative but not positive ions.

C) ability to change its size depending on the ion needing transport.

D) binding with only one type of neurotransmitter.

E) permitting passage only to a specific ion.

 

E) permitting passage only to a specific ion.

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21) A "resting" motor neuron is expected to

A) release lots of acetylcholine.

B) have high permeability to sodium ions.

C) be equally permeable to sodium and potassium ions.

D) exhibit a resting potential that is more negative than the "threshold" potential.

E) have a higher concentration of sodium ions on the inside of the cell than on the outside.

 

D) exhibit a resting potential that is more negative than the "threshold" potential.

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22) The "threshold" potential of a membrane

A) is the point of separation from a living to a dead neuron.

B) is the lowest frequency of action potentials a neuron can produce.

C) is the minimum hyperpolarization needed to prevent the occurrence of action potentials.

D) is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels.

E) is the peak amount of depolarization seen in an action potential.

 

D) is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels.

119

23) Action potentials move along axons

A) more slowly in axons of large than in small diameter.

B) by the direct action of acetylcholine on the axonal membrane.

C) by activating the sodium-potassium "pump" at each point along the axonal membrane.

D) more rapidly in myelinated than in non-myelinated axons.

E) by reversing the concentration gradients for sodium and potassium ions.

 

D) more rapidly in myelinated than in non-myelinated axons.

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24) A toxin that binds specifically to voltage-gated sodium channels in axons would be expected to

A) prevent the hyperpolarization phase of the action potential.

B) prevent the depolarization phase of the action potential.

C) prevent graded potentials.

D) increase the release of neurotransmitter molecules.

E) have most of its effects on the dendritic region of a neuron.

 

B) prevent the depolarization phase of the action potential.

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25) After the depolarization phase of an action potential, the resting potential is restored by

A) the opening of sodium activation gates.

B) the opening of voltage-gated potassium channels and the closing of sodium channels.

C) a decrease in the membrane's permeability to potassium and chloride ions.

D) a brief inhibition of the sodium-potassium pump.

E) the opening of more voltage-gated sodium channels.

 

B) the opening of voltage-gated potassium channels and the closing of sodium channels.

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26) The "undershoot" phase of after-hyperpolarization is due to

A) slow opening of voltage-gated sodium channels.

B) sustained opening of voltage-gated potassium channels.

C) rapid opening of voltage-gated calcium channels.

D) slow restorative actions of the sodium-potassium ATPase.

E) ions that move away from their open ion channels.

 

B) sustained opening of voltage-gated potassium channels.

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27) Immediately after an action potential passes along an axon, it is not possible to generate a second action potential; thus, we state that the membrane is briefly

A) hyperexcitable.

B) refractory.

C) fully depolarized.

D) above threshold.

E) at the equilibrium potential.

 

B) refractory.

124

28) An action potential can start in the middle of an axon and proceed in both opposite directions when

A) the neuron is an inhibitory neuron and operating normally.

B) only the middle section of the axon has been artificially stimulated by an electrode.

C) the dendritic region fires an action potential.

D) it is in its typical refractory state.

E) its membrane potential is above the threshold.

 

B) only the middle section of the axon has been artificially stimulated by an electrode.

125

29) The primary means by which a neuron can communicate to a second neuron is by

A) the frequency of its action potentials.

B) the peak of the depolarization phase of an action potential.

C) the peak of the undershoot/hyperpolarization of an action potential.

D) varying how much neurotransmitter it releases for a given action potential.

E) remaining in the depolarization phase of the action potential for an extended interval.

 

A) the frequency of its action potentials.

126

30) In the sequence of permeability changes for a complete action potential, the first of these events that occurs is

A) the activation of the sodium-potassium "pump."

B) the inhibition of the sodium-potassium "pump."

C) the opening of voltage-gated sodium channels.

D) the closing of voltage-gated potassium channels.

E) the opening of voltage-gated potassium channels.

 

C) the opening of voltage-gated sodium channels.

127

33) Neurotransmitters are released from axon terminals via

A) osmosis.

B) active transport.

C) diffusion.

D) transcytosis.

E) exocytosis.

 

E) exocytosis.

128

34) The fastest possible conduction velocity of action potentials is observed in

A) thin, non-myelinated neurons.

B) thin, myelinated neurons.

C) thick, non-myelinated neurons.

D) thick, myelinated neurons.

 

D) thick, myelinated neurons.

129

37) The release of acetylcholine from the terminal of a motor neuron is most directly linked to

A) the entry of potassium into the axon terminal.

B) the exit of potassium from the axon terminal.

C) the entry of sodium into the axon terminal.

D) the exit of sodium from the axon terminal.

E) the entry of calcium into the axon terminal.

 

E) the entry of calcium into the axon terminal.

130

38) The observation that the acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it is an example of

A) a voltage-gated sodium channel.

B) a voltage-gated potassium channel.

C) a ligand-gated sodium channel.

D) a second-messenger-gated sodium channel.

E) a chemical that inhibits action potentials.

 

C) a ligand-gated sodium channel.

131

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) 3 → 2 → 5 → 1 → 4

132

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) ligand-gated ion channels.

133

61) The membrane potential is closest to the equilibrium potential for potassium at label

A) A.

B) B.

C) C.

D) D.

E) E.

 

Q image thumb

D) D.

134

62) The membrane's permeability to sodium ions is at its maximum at label

A) A.

B) B.

C) C.

D) D.

E) E.

 

Q image thumb

B) B.

135

63) The minimum graded depolarization needed to operate the voltage-gated sodium and potassium channels is indicated by the label

A) A.

B) B.

C) C.

D) D.

E) E.

 

Q image thumb

A) A.

136

64) The cell is not hyperpolarized; however, repolarization is in progress, as the sodium channels are closing or closed, and many potassium channels have opened at label

A) A.

B) B.

C) C.

D) D.

E) E.

 

C) C.

137

65) The neuronal membrane is at its resting potential at label

A) A.

B) B.

C) C.

D) D.

E) E.

 

Q image thumb

E) E.

138

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) two action potentials will be initiated, one going toward the axon terminal and one going back toward the hillock.

139

67) Assume that excessive consumption of ethanol increases the influx of negative chloride ions into "common sense" neurons whose action potentials are needed for you to act appropriately and not harm yourself or others. Thus, any resulting poor decisions associated with ethanol ingestion are likely due to

A) increased membrane depolarization of "common sense" neurons.

B) decreased membrane depolarization of "common sense" neurons.

C) more action potentials in your "common sense" neurons.

D) more EPSPs in your "common sense" neurons.

E) fewer IPSPs in your "common sense" neurons.

 

B) decreased membrane depolarization of "common sense" neurons.

140

68) What happens when a resting neuron's membrane depolarizes?

A) There is a net diffusion of Na+ out of the cell.

B) The equilibrium potential for K+ (EK) becomes more positive.

C) The neuron's membrane voltage becomes more positive.

D) The neuron is less likely to generate an action potential.

E) The cell's inside is more negative than the outside.

 

C) The neuron's membrane voltage becomes more positive.

141

72) Why are action potentials usually conducted in one direction?

A) The nodes of Ranvier conduct potentials in one direction.

B) The brief refractory period prevents reopening of voltage-gated Na+ channels.

C) The axon hillock has a higher membrane potential than the terminals of the axon.

D) Ions can flow along the axon in only one direction.

E) Voltage-gated channels for both Na+ and K+ open in only one direction.

 

B) The brief refractory period prevents reopening of voltage-gated Na+ channels.

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1) Innate immunity

A) is activated immediately upon infection.

B) depends on a newly infected animal's previous exposure to the same pathogen.

C) is based on recognition of antigens that are specific to different pathogens.

D) is found only in vertebrate animals.

E) utilizes highly specific antigen receptors on B cells.

 

A) is activated immediately upon infection.

143

2) Acidity in human urine is an example of

A) cell-mediated immune responses.

B) antibody activation.

C) acquired immunity.

D) adaptive immunity.

E) innate immunity.

 

E) innate immunity.

144

3) A fruit fly, internally infected by a potentially pathogenic fungus, is protected by

A) its plasma cells.

B) its immunoglobulins.

C) its antibodies.

D) its antimicrobial peptides.

E) its B cells.

 

D) its antimicrobial peptides.

145

4) Engulfing-phagocytic cells of innate immunity include all of the following except

A) neutrophils.

B) macrophages.

C) dendritic cells.

D) natural killer cells.

 

D) natural killer cells.

146

5) The lymphatic fluid

A) is a filtrate of the blood, as is urine.

B) is completely separate from the circulatory system for blood.

C) carries both red and white blood cells.

D) functions in adaptive immunity but not in innate immunity.

E) carries a toxic gas that kills cancerous cells.

 

A) is a filtrate of the blood, as is urine.

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6) An inflammation-causing signal released by mast cells at the site of an infection is

A) an interferon.

B) lymphatic fluid.

C) histamine.

D) mucus.

E) sodium ions.

 

C) histamine.

148

7) A systemic inflammatory response that is often life-threatening is

A) mild fever.

B) aches and dull pain.

C) septic shock.

D) high blood pressure.

E) increased white blood cell count.

 

C) septic shock.

149

8) The eyes and the respiratory tract are both protected against infections by

A) the mucous membranes that cover their surface.

B) the secretion of complement proteins.

C) the release of slightly alkaline secretions.

D) the secretion of lysozyme onto their surfaces.

E) interferons produced by immune cells.

 

D) the secretion of lysozyme onto their surfaces.

150

9) Salmonella bacterial poisoning can be initiated when

A) the microbe survives the acidic environment of the stomach and resists lysosomal degradation in macrophages.

B) the chemotactic messengers released by the microbe do not attract sufficient neutrophils to entirely destroy the infection.

C) there is a delay in selection of the population of eosinophils that recognize and fight these microbes.

D) the microbes release chemical messengers that make them resistant to phagocytosis.

E) The combination of foods eaten at the meal reduces the pH of the stomach sufficiently so that ingested microbes are not destroyed.

 

A) the microbe survives the acidic environment of the stomach and resists lysosomal degradation in macrophages.

151

10) The complement system is

A) a set of proteins involved in innate but not acquired immunity.

B) a set of proteins secreted by cytotoxic T cells and other CD8 cells.

C) a group of proteins that includes interferons and interleukins.

D) a group of antimicrobial proteins that act together in a cascade fashion.

E) a set of proteins that act individually to attack and lyse microbes.

 

D) a group of antimicrobial proteins that act together in a cascade fashion.

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11) Antihistamine treatment reduces

A) blood vessel dilation.

B) phagocytosis of antigens.

C) MHC presentation by macrophages.

D) the secondary immune response.

E) clonal selection by antigens.

 

A) blood vessel dilation.

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12) Cave art by early humans recognized the existence of the major signs of inflammation. The most inclusive set of symptoms of inflammation that might appear in such early human art is

A) heat, pain, and redness.

B) pain and whitening of the surrounding tissue.

C) swelling and pain.

D) antibody-producing cells.

E) swelling, heat, redness, and pain.

 

E) swelling, heat, redness, and pain.

154

13) Ancient peoples sought to identify the indicators of inflammation because

A) seeing such signs would be cause for their seeking out a healer in their community.

B) the presence of the signs of inflammation in a patient could be a condemnation of the healer.

C) the ancients probably knew of plant derivatives that could reduce the pain of inflammation.

D) the presence of these signs suggests that healing was taking place; otherwise, the patient would likely die.

E) the signs of inflammation served as a caution to keep people away from the patient.

 

D) the presence of these signs suggests that healing was taking place; otherwise, the patient would likely die.

155

 

14) The cells and signaling molecules that initiate inflammatory responses are

A) the phagocytes and the lysozymes.

B) the phagocytes and the chemokines.

C) the dendritic cells and the interferons.

D) the mast cells and the histamines.

E) the lymphocytes and the interferons.

 

D) the mast cells and the histamines.

156

15) Inflammatory responses typically include

A) clotting proteins migrating away from the site of infection.

B) increased activity of phagocytes in an inflamed area.

C) reduced permeability of blood vessels to conserve plasma.

D) release of substances to decrease the blood supply to an inflamed area.

E) inhibiting the release of white blood cells from bone marrow.

 

B) increased activity of phagocytes in an inflamed area.

157

16) Bacteria entering the body through a small cut in the skin

A) inactivate the erythrocytes.

B) stimulate apoptosis of nearby body cells.

C) stimulate release of interferons.

D) stimulate natural killer cell activity.

E) activate a group of proteins called complement.

 

E) activate a group of proteins called complement.

158

17) An invertebrate, such as an insect, has innate immunity activity in its intestine that likely includes

A) complement.

B) lysozyme.

C) mucus.

D) neutrophils.

E) dendritic cells.

 

B) lysozyme.

159

18) In some insects, such as Drosophila, fungal cell wall elements can activate the protein Toll, which

A) acts as a receptor that, when activated, signals synthesis of antimicrobial peptides.

B) functions directly to attack the fungi presented to it.

C) produces antimicrobial peptides by interaction with chitin.

D) secretes special recognition signal molecules that identify specific pathogens.

E) causes some hemocytes to phagocytize the pathogens.

 

A) acts as a receptor that, when activated, signals synthesis of antimicrobial peptides.

160

19) Mammals have Toll-like receptors (TLRs) that can recognize a kind of macromolecule that is absent from vertebrates but present in/on certain groups of pathogens, including viral

A) lipopolysaccharides.

B) double-stranded DNA.

C) double-stranded RNA.

D) glycoproteins.

E) phospholipids.

 

C) double-stranded RNA.

161

20) Histamines trigger dilation of nearby blood vessels as well as an increase in their permeability, producing

A) redness and heat only.

B) swelling only.

C) pain.

D) redness, heat, and swelling.

E) all of the signs of a major infection.

 

D) redness, heat, and swelling.

162

21) Septic shock, a systemic response including high fever and low blood pressure, is a response to

A) certain bacterial infections.

B) specific forms of viruses.

C) the presence of natural killer cells.

D) a fever of >103°F in adults.

E) increased production of neutrophils.

 

A) certain bacterial infections.

163

22) Infection by a bacterium that has elements on its surface that enhance its resistance to lysozyme will likely result in

A) destruction of the bacterium by NK cells.

B) successful reproduction of the bacterium and continued progression of the disease.

C) removal of the bacterium by dendritic cells and its concentration in lymph nodes.

D) the infected individual's humoral immunity becoming the only route of infection response.

E) lymphocytes migrating from the thymus to attack the bacterium.

 

B) successful reproduction of the bacterium and continued progression of the disease.

164

23) Adaptive immunity depends on

A) traits common to groups of pathogens.

B) pathogen-specific recognition.

C) maternal provision of antibodies to offspring.

D) plants being exposed to new pathogens.

E) having exhausted all options for innate immunity responses.

 

B) pathogen-specific recognition.

165

24) Bacterial infection in a previously uninfected house cat would most quickly activate its

A) Toll-like receptors that bind to lipopolysaccharides.

B) memory cells to produce antibodies.

C) plasma cells to produce antigens.

D) cytotoxic T cells.

E) humoral immune responses.

 

A) Toll-like receptors that bind to lipopolysaccharides.

166

25) A key part of the humoral immune response is

A) the attack of cytotoxic T cells on infected host cells.

B) the production of antibodies by plasma cells.

C) perforation of infected host cells by perforin.

D) the attack of phagocytes on living pathogens.

E) the initiation of programmed cell death in infected host cells.

 

B) the production of antibodies by plasma cells.

167

26) The receptors on T cells and B cells bind to

A) antibodies.

B) antigens.

C) natural killer cells.

D) double-stranded RNA.

E) immunoglobulins.

 

B) antigens.

168

27) An epitope is

A) part of the interferons that penetrate foreign cells.

B) a protein protruding from the surface of B cells.

C) two structurally similar antibodies dissolved in the blood plasma.

D) that part of an antigen that actually binds to an antigen receptor.

E) a mirror image of an antigen.

 

D) that part of an antigen that actually binds to an antigen receptor.

169

28) B cells have antigen receptors that bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells. T cells have antigen receptors that

A) are active only in lymph nodes.

B) bind only to antigens present on the surface of the invading/foreign cells.

C) bind only to freely dissolved antigens in the plasma.

D) bind to antigens presented on major histocompatability complexes by host cells.

E) bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells.

 

D) bind to antigens presented on major histocompatability complexes by host cells.

170

29) Within a differentiated B cell, the rearrangement of DNA sequences between variable regions and joining regions is accomplished by

A) polyadenylase.

B) RNA polymerase.

C) reverse transcriptase.

D) epitopase.

E) recombinase.

 

E) recombinase.

 

 

171

30) Clonal selection of B cells activated by antigen exposure leads to production of

A) large numbers of neutrophils.

B) large quantities of the antigen initially recognized.

C) vast numbers of B cells with random antigen-recognition receptors.

D) long-lived erythrocytes that can later secrete antibodies for the antigen.

E) short-lived plasma cells that secrete antibodies for the antigen.

 

E) short-lived plasma cells that secrete antibodies for the antigen.

172

31) Antigens are

A) proteins found in the blood that cause foreign blood cells to clump.

B) proteins embedded in B cell membranes.

C) proteins that consist of two light and two heavy polypeptide chains.

D) foreign molecules that trigger the generation of antibodies.

E) proteins released during an inflammatory response.

 

D) foreign molecules that trigger the generation of antibodies.

173

32) A newborn who is accidentally given a drug that destroys the thymus would most likely

A) lack class I MHC molecules on cell surfaces.

B) lack humoral immunity.

C) be unable to genetically rearrange antigen receptors.

D) be unable to differentiate and mature T cells.

E) have a reduced number of B cells and be unable to form antibodies.

 

D) be unable to differentiate and mature T cells.

174

33) Clonal selection implies that

A) brothers and sisters have similar immune responses.

B) antigens increase mitosis in specific lymphocytes.

C) only certain cells can produce interferon.

D) a B cell has multiple types of antigen receptors.

E) the body selects which antigens it will respond to.

 

B) antigens increase mitosis in specific lymphocytes.

175

34) Clonal selection is an explanation for how

A) a single type of stem cell can produce both red blood cells and white blood cells.

B) V, J, and C gene segments are rearranged.

C) an antigen can provoke production of high levels of specific antibodies.

D) HIV can disrupt the immune system.

E) macrophages can recognize specific T cells and B cells.

 

C) an antigen can provoke production of high levels of specific antibodies.

176

35) Secondary immune responses upon a second exposure to a pathogen are due to the activation of

A) memory cells.

B) macrophages.

C) stem cells.

D) B cells.

E) T cells.

 

A) memory cells.

177

36) The MHC is important in a T cell's ability to

A) distinguish self from nonself.

B) recognize specific parasitic pathogens.

C) identify specific bacterial pathogens.

D) identify specific viruses.

E) recognize differences among types of cancer.

 

A) distinguish self from nonself.

178

37) A patient who can produce antibodies against some bacterial pathogens, but not against viral infections, probably has a disorder in his

A) B cells.

B) plasma cells.

C) natural killer cells.

D) T cells.

E) macrophages.

 

D) T cells.

179

38) The activation of helper T cells is likely

A) when an antigen is displayed by a dendritic cell.

B) when a cytotoxic T cell releases cytokines.

C) when natural killer (NK) cells come in contact with a tumor cell.

D) in the bone marrow during the self-tolerance test.

E) when B cells respond to T-independent antigens.

 

A) when an antigen is displayed by a dendritic cell.

180

39) An immunoglobulin (Ig) molecule, of whatever class, with regions symbolized as C or V, H or L, has a light chain made up of

A) one C region and one V region.

B) three C regions and one V region.

C) one H region and one L region.

D) three H regions and one L region.

E) two C regions and two V regions.

 

A) one C region and one V region.

181

40) The ability of one person to produce over a million different antibody molecules does not require over a million different genes; rather, this wide range of antibody production is due to

A) alternative splicing of exons after transcription.

B) increased rate of mutation in the RNA molecules.

C) DNA rearrangements.

D) rearrangements of cytosolic proteins in the thymus cells.

E) crossing over between the light and heavy chains of each antibody molecule during meiosis I.

 

C) DNA rearrangements.

182

41) Immunological memory accounts for

A) the human body's ability to distinguish self from nonself.

B) the observation that some strains of the pathogen that causes dengue fever cause worse disease than others.

C) the ability of a helper T cell to signal B cells via cytokines.

D) the ancient observation that someone who had recovered from the plague could safely care for those newly deceased.

E) the ability of the immune system to present antigen fragments in association with MHC antigens.

 

D) the ancient observation that someone who had recovered from the plague could safely care for those newly deceased.

183

 

42) The function of antibodies is to

A) inject toxins into living pathogens.

B) secrete cytokines that attract macrophages to infection sites.

C) release perforins to disrupt infected cells.

D) act as Toll-like receptors.

E) mark pathogenic cells for destruction.

 

E) mark pathogenic cells for destruction.

184

43) This type of immunity is present only when a newborn infant is being fed by actively nursing on its mother and ends when nursing ends.

A) innate immunity

B) active immunity

C) passive immunity

D) cell-mediated immunity

E) adaptive immunity

 

C) passive immunity

185

44) Yearly vaccination of humans for influenza viruses is necessary because

A) of an increase in immunodeficiency diseases.

B) flu can generate anaphylactic shock.

C) surviving the flu one year exhausts the immune system to unresponsiveness the second year.

D) rapid mutation in flu viruses alters the surface proteins in infected host cells.

E) flu leads to autoimmune disorders.

 

D) rapid mutation in flu viruses alters the surface proteins in infected host cells.

186

45) The cell-mediated immunity that destroys virally infected cells involves

A) cytotoxic T cells.

B) natural killer cells.

C) helper T cells.

D) macrophages.

E) B cells.

 

A) cytotoxic T cells.

187

46) Which of the following cells are involved in cell-mediated immunity and also respond to class I MHC molecule-antigen complexes?

A) cytotoxic T cells

B) natural killer cells

C) helper T cells

D) macrophages

E) B cells

 

A) cytotoxic T cells

188

47) The cells involved in innate immunity, whose absence increases the chances of developing malignant tumors, are

A) cytotoxic T cells.

B) natural killer cells.

C) helper T cells.

D) macrophages.

E) B cells.

 

B) natural killer cells.

189

48) Select the pathway that would lead to the activation of cytotoxic T cells.

A) B cell contact antigen → helper T cell is activated → clonal selection occurs

B) body cell becomes infected with a virus → new viral proteins appear → class I MHC molecule-antigen complex displayed on cell surface

C) self-tolerance of immune cells → B cells contact antigen → cytokines released

D) complement is secreted → B cell contacts antigen → helper T cell activated → cytokines released

E) cytotoxic T cells → class II MHC molecule-antigen complex displayed → cytokines released → cell lysis

 

B) body cell becomes infected with a virus → new viral proteins appear → class I MHC molecule-antigen complex displayed on cell surface

190

49) Among the last line of defenses against prolonged exposure to an extracellular pathogen is

A) lysozyme production.

B) phagocytosis by neutrophils.

C) antibody production by plasma cells.

D) histamine release by basophils.

E) lysis by natural killer cells.

 

C) antibody production by plasma cells.

191

50) Arrange these components of the mammalian immune system as it first responds to a pathogen in the correct sequence.

I.     Pathogen is destroyed.

II.     Lymphocytes secrete antibodies.

III.     Antigenic determinants from pathogen bind to antigen receptors on lymphocytes.

IV.     Lymphocytes specific to antigenic determinants from pathogen become numerous.

V.     Only memory cells remain.

A) I → III → II → IV → V

B) III → II → I → V → IV

C) II → I → IV → III → V

D) IV → II → III → I → V

E) III → IV → II → I → V

 

E) III → IV → II → I → V

192

 

51) A cell type that interacts with both the humoral and cell-mediated immune pathways is a

A) plasma cell.

B) cytotoxic T cell.

C) natural killer cell.

D) CD8 cell.

E) helper T cell.

 

E) helper T cell.

193

52) A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable to

A) respond to T-independent antigens.

B) lyse tumor cells.

C) stimulate a cytotoxic T cell.

D) interact with a class I MHC-antigen complex.

E) interact with a class II MHC-antigen complex.

 

E) interact with a class II MHC-antigen complex.

194

53) CD4 and CD8 are

A) proteins secreted by antigen-presenting cells.

B) receptors present on the surface of natural killer (NK) cells.

C) T-independent antigens.

D) molecules present on the surface of T cells where they interact with MHC molecules.

E) molecules on the surface of antigen-presenting cells where they enhance B cell activity.

 

D) molecules present on the surface of T cells where they interact with MHC molecules.

195

54) T cells of the immune system include

A) CD4, CD8, and plasma cells.

B) cytotoxic and helper cells.

C) plasma, antigen-presenting, and memory cells.

D) lymphocytes, macrophages, and dendritic cells.

E) class I MHC, class II MHC, and memory cells.

 

B) cytotoxic and helper cells.

196

55) B cells interacting with helper T cells are stimulated to differentiate when

A) B cells produce IgE antibodies.

B) B cells release cytokines.

C) helper T cells present the class II MHC molecule-antigen complex on their surface.

D) helper T cells differentiate into cytotoxic T cells.

E) helper T cells release cytokines.

 

E) helper T cells release cytokines.

197

 

56) Normal immune responses can be described as polyclonal because

A) blood contains many different antibodies and antigens.

B) construction of a hybridoma requires multiple types of cells.

C) multiple immunoglobulins are produced from descendants of a single B cell.

D) diverse antibodies are produced for different epitopes of a specific antigen.

E) macrophages, T cells, and B cells all are involved in a normal immune response.

 

D) diverse antibodies are produced for different epitopes of a specific antigen.

198

57) Antibodies of the different classes IgM, IgG, IgA, IgD, and IgE differ from each other

A) in the way they are produced.

B) in their heavy-chain structure.

C) in the type of cell that produces them.

D) by the antigenic determinants that they recognize.

E) by the number of carbohydrate subunits they have.

 

B) in their heavy-chain structure.

199

 

58) When antibodies bind antigens, the clumping of antigens results from

A) the multivalence of the antibody having at least two binding regions.

B) disulfide bridges between the antigens.

C) complement that makes the affected cells sticky.

D) bonds between class I and class II MHC molecules.

E) denaturation of the antibodies.

 

A) the multivalence of the antibody having at least two binding regions.

200

 

59) Phagocytosis of microbes by macrophages is enhanced by

A) the binding of antibodies to the surface of microbes.

B) antibody-mediated agglutination of microbes.

C) the release of cytokines by activated B cells.

D) the binding of antibodies to the surface of microbes and antibody-mediated agglutination of microbes only.

E) the binding of antibodies to the surface of microbes, antibody-mediated agglutination of microbes, and the release of cytokines by activated B cells.

 

D) the binding of antibodies to the surface of microbes and antibody-mediated agglutination of microbes only.

201

60) The primary function of humoral immunity is

A) to defend against fungi and protozoa.

B) to reject transplanted tissues.

C) to protect the body against cells that become cancerous.

D) to protect the body against extracellular pathogens.

E) to defend against bacteria and viruses that have already infected cells.

 

D) to protect the body against extracellular pathogens.

202

61) Naturally acquired passive immunity results from the

A) injection of vaccine.

B) ingestion of interferon.

C) placental transfer of antibodies.

D) absorption of pathogens through mucous membranes.

E) injection of antibodies.

 

C) placental transfer of antibodies.

203

 

62) In active immunity, but not passive immunity, there is

A) acquisition and activation of antibodies.

B) proliferation of lymphocytes in bone marrow.

C) the transfer of antibodies from the mother across the placenta.

D) the requirement for direct exposure to a living or simulated pathogen.

E) the requirement of secretion of interleukins from macrophages.

 

D) the requirement for direct exposure to a living or simulated pathogen.

204

63) Jenner's successful use of cowpox virus as a vaccine against the smallpox virus is due to the fact that

A) the immune system responds nonspecifically to antigens.

B) the cowpox virus made antibodies in response to the presence of smallpox.

C) cowpox and smallpox are antibodies with similar immunizing properties.

D) there are some antigenic determinants common to both pox viruses.

E) cowpox and smallpox are caused by the same virus.

 

D) there are some antigenic determinants common to both pox viruses.

205

64) An individual who has been bitten by a poisonous snake that has a fast-acting toxin would likely benefit from

A) vaccination with a weakened form of the toxin.

B) injection of antibodies to the toxin.

C) injection of interleukin-1.

D) injection of interleukin-2.

E) injection of interferon.

 

B) injection of antibodies to the toxin.

206

65) For the successful development of a vaccine to be used against a pathogen, it is necessary that

A) the surface antigens of the pathogen not change.

B) a rearrangement of the B cell receptor antibodies takes place.

C) all of the surface antigens on the pathogen be identified.

D) the pathogen has only one epitope.

E) the MHC molecules are heterozygous.

 

A) the surface antigens of the pathogen not change.

207

66) A diseased patient is exposed to an unknown agent while out of the country. The patient's blood is found to have a high proportion of lymphocytes with CD8 surface proteins in her blood, a likely result of

A) the patient having encountered a bacterial infection which elicited CD8+ T cells.

B) the disease having been caused by a multicellular parasite, such as can be encountered in polluted water sources.

C) the CD8 proteins having been discharged from these lymphocytes to lyse the infected cells.

D) a viral infection eliciting proliferation of CD8+ cytotoxic T cells.

E) the CD8 proteins having "marked" the surface of cells that accumulate after the infection is over and signal patient recovery.

 

D) a viral infection eliciting proliferation of CD8+ cytotoxic T cells.

208

67) The switch of one B cell from producing one class of antibody to another antibody class that is responsive to the same antigen is due to

A) mutation in the genes of that B cell, induced by exposure to the antigen.

B) the rearrangement of V region genes in that clone of responsive B cells.

C) a switch in the kind of antigen-presenting cell that is involved in the immune response.

D) a patient's reaction to the first kind of antibody made by the plasma cells.

E) the rearrangement of immunoglobulin heavy-chain C region DNA.

 

E) the rearrangement of immunoglobulin heavy-chain C region DNA.

209

68) The number of MHC protein combinations possible in a given population is enormous. However, an individual in that diverse population has a far more limited array of MHC molecules because

A) the MHC proteins are made from several different gene regions that are capable of rearranging in a number of ways.

B) MHC proteins from one individual can only be of class I or class II.

C) each of the MHC genes has a large number of alleles, but each individual only inherits two for each gene.

D) once a B cell has matured in the bone marrow, it is limited to two MHC response categories.

E) once a T cell has matured in the thymus, it can only respond to two MHC categories.

 

C) each of the MHC genes has a large number of alleles, but each individual only inherits two for each gene.

210

69) A bone marrow transplant may not be appropriate from a given donor (Jane) to a given recipient (Jane's cousin Bob), even though Jane has previously given blood for one of Bob's needed transfusions, because

A) even though Jane's blood type is a match to Bob's, her MHC proteins may not be a match.

B) a blood type match is less stringent than a match required for transplant because blood is more tolerant of change.

C) for each gene, there is only one blood allele but many tissue alleles.

D) Jane's class II genes are not expressed in bone marrow.

E) Bob's immune response has been made inadequate before he receives the transplant.

 

A) even though Jane's blood type is a match to Bob's, her MHC proteins may not be a match.

211

70) Infection with HIV typically

A) increases the level of helper T cells for the first year after infection.

B) eliminates all T cells immediately.

C) leads to an immediate decrease in the number of HIV in the blood.

D) alters mitochondrial but not genomic DNA sequences.

E) is found in B cells but not in T cells.

 

A) increases the level of helper T cells for the first year after infection.

212

71) The transfusion of type A blood to a person who has type O blood would result in

A) the recipient's B antigens reacting with the donated anti-B antibodies.

B) the recipient's anti-A antibodies clumping the donated red blood cells.

C) the recipient's anti-A and anti-O antibodies reacting with the donated red blood cells if the donor was a heterozygote (Ai) for blood type.

D) no reaction because type O is a universal donor.

E) no reaction because the O-type individual does not have antibodies.

 

B) the recipient's anti-A antibodies clumping the donated red blood cells.

213

72) An immune response to a tissue graft will differ from an immune response to a bacterium because

A) MHC molecules of the donor may stimulate rejection of the graft tissue, but bacteria lack MHC molecules.

B) the tissue graft, unlike the bacterium, is isolated from the circulation and will not enter into an immune response.

C) a response to the graft will involve B cells and a response to the bacterium will not.

D) a bacterium cannot escape the immune system by replicating inside normal body cells.

E) the graft will stimulate an autoimmune response in the recipient.

 

A) MHC molecules of the donor may stimulate rejection of the graft tissue, but bacteria lack MHC molecules.

214

73) In the human disease known as lupus, there is an immune reaction against a patient's own DNA from broken or dying cells, which categorizes lupus as

A) an allergy.

B) an immunodeficiency.

C) an autoimmune disease.

D) an antigenic variation.

E) a cancer.

 

C) an autoimmune disease.

215

74) A patient who undergoes a high level of mast cell degranulation, dilation of blood vessels, and acute drop in blood pressure is likely suffering from

A) an autoimmune disease.

B) a typical allergy that can be treated by antihistamines.

C) an organ transplant, such as a skin graft.

D) the effect of exhaustion on the immune system.

E) anaphylactic shock immediately following exposure to an allergen.

 

E) anaphylactic shock immediately following exposure to an allergen.

216

75) An example of a pathogen that undergoes rapid changes resulting in antigenic variation is

A) the influenza virus, which expresses alternative envelope proteins.

B) the strep bacteria, which can be communicated from patient to patient with high efficiency.

C) human papilloma virus, which can remain latent for several years.

D) the causative agent of the autoimmune disease known as rheumatoid arthritis.

E) multiple sclerosis, which attacks the myelinated cells of the nervous system.

 

A) the influenza virus, which expresses alternative envelope proteins.

217

76) The ability of some viruses to remain inactive (latent) for a period of time is exemplified by

A) influenza, a particular strain of which returns every 10-20 years.

B) herpes simplex viruses (oral or genital) whose reproduction is triggered by physiological or emotional stress in the host.

C) Kaposi's sarcoma, which causes a skin cancer in people with AIDS, but rarely in those not infected by HIV.

D) the virus that causes a form of the common cold, which recurs in patients many times in their lives.

E) myasthenia gravis, an autoimmune disease that blocks muscle contraction from time to time.

 

B) herpes simplex viruses (oral or genital) whose reproduction is triggered by physiological or emotional stress in the host.

218

77) Most newly emerging diseases result in

A) greater severity as there are more and more occurrences of the infection.

B) major pandemics, spreading the infection far and wide in the population.

C) the waning of the disease, due to evolutionary selection for resistant hosts and milder pathogens.

D) a destruction of the host's immune system and eventual cancer.

E) no discoverable relationship with other pathogens in the same or related species.

 

C) the waning of the disease, due to evolutionary selection for resistant hosts and milder pathogens.

219

 

78) Preventing the appearance of the symptoms of an allergy attack would be the likely result of

A) blocking the attachment of the IgE antibodies to the mast cells.

B) blocking the antigenic determinants of the IgM antibodies.

C) reducing the number of helper T cells in the body.

D) reducing the number of cytotoxic cells.

E) reducing the number of natural killer cells.

 

A) blocking the attachment of the IgE antibodies to the mast cells.

220

79) A patient complaining of watery, itchy eyes and sneezing after being given a flower bouquet as a birthday gift should first be treated with

A) a vaccine.

B) complement.

C) sterile pollen.

D) antihistamines.

E) monoclonal antibodies.

 

D) antihistamines.

221

80) A patient who has a parasitic worm infection and another patient responding to an allergen such as ragweed pollen have which of the following in common?

A) an increase in cytotoxic T cell number

B) suffering from anaphylactic shock

C) risking development of an autoimmune disease

D) suffering from a decreased level of innate immunity

E) an increase in the levels of IgE

 

E) an increase in the levels of IgE

222

An otherwise healthy student in your class is infected with EBV, the virus that causes infectious mononucleosis. The same student had already been infected when she was a child, at which time she had merely experienced a mild sore throat and swollen lymph nodes in her neck. This time, though infected, she does not get sick.

 

89) Her immune system's recognition of the second infection involves the

A) helper T cells.

B) memory B cells.

C) plasma cells.

D) cytotoxic T cells.

E) natural killer cells.

 

 

D) cytotoxic T cells.

223

88) After a long and cold winter, Jim was excited to start exploring the woods behind his new home. His first adventure included exposure to poison ivy without any reaction. A month later, though, a second walk through the woods was not so great, since two days later Jim had a terrible rash that lasted for weeks. The fact that the rash took two days to develop indicates that this immune response was an example of

A) humoral immunity.

B) cell-mediated immunity.

C) innate immunity.

D) the activation of Toll-like receptors.

E) the activation of the complement system.

 

 

B) cell-mediated immunity.

224

90) The EBV antigen fragments will be presented by the virus-infected cells along with

A) complement.

B) antibodies.

C) class I MHC molecules.

D) class II MHC molecules.

E) dendritic cells.

 

C) class I MHC molecules.

225

 

Immunodeficiencies can be genetic in origin, and two examples are Bruton's agammaglobulinemia, an X-linked disorder, and DiGeorge syndrome, caused by a deletion from chromosome 22. Bruton's disorder results in underdeveloped B cells, whereas DiGeorge syndrome results in a missing or seriously underdeveloped thymus.

 

91) Select the description that likely indicates a child with Bruton's disease.

A) baby girl Denise, with low level of antibody response to streptococcal infection

B) baby boy John, with immature T cells, missing CD4 receptors

C) baby boy Jeff, with no plasma cells following infection by bacterial pneumonia

D) baby girl Susan, with no evidence of a thymus gland

E) baby boy Matt, with very low circulating antigens

 

C) baby boy Jeff, with no plasma cells following infection by bacterial pneumonia

226

92) Bruton's disorder will likely include

A) the failure of heavy-chain gene rearrangement in B cells.

B) the failure to incorporate CD4 receptors into cell membranes.

C) an underexpression of the gene for the β chain of the T cell receptor.

D) an underexpression of the gene for the CD8 receptor molecule.

E) the inability of the bone marrow cells to interact with MHC molecules.

 

A) the failure of heavy-chain gene rearrangement in B cells.

227

93) Assume that a DGS-like phenotype was produced in a specific "gene-knockout" mouse, one lacking expression of HA3, a Hox gene known to be involved in developmental regulation in the mouse.

The phenotype of the HA3 knockout can be ascertained by

A) a bone marrow biopsy.

B) an assay for environmental agents known to cause birth defects.

C) a chest X-ray.

D) the measurement of the proportion of CD4 cells to total lymphocytes.

E) an autopsy examination of the adrenal glands.

 

D) the measurement of the proportion of CD4 cells to total lymphocytes.

228

94) Which of these is not part of insect immunity?

A) enzyme activation of microbe-killing chemicals

B) activation of natural killer cells

C) phagocytosis by hemocytes

D) production of antimicrobial peptides

E) a protective exoskeleton

 

B) activation of natural killer cells

229

95) An epitope associates with which part of an antigen receptor or antibody?

A) the disulfide bridge

B) the heavy-chain constant regions only

C) variable regions of a heavy chain and light chain combined

D) the light-chain constant regions only

E) the tail

 

C) variable regions of a heavy chain and light chain combined

230

96) Which statement best describes the difference in responses of effector B cells (plasma cells) and cytotoxic T cells?

A) B cells confer active immunity; cytotoxic T cells confer passive immunity.

B) B cells kill pathogens directly; cytotoxic T cells kill host cells.

C) B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells.

D) B cells carry out the cell-mediated response; cytotoxic T cells carry out the humoral response.

E) B cells respond the first time a pathogen is present; cytotoxic T cells respond subsequent times.

 

C) B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells.

231

97) Which of the following statements is not true?

A) An antibody has more than one antigen-binding site.

B) An antigen can have different epitopes.

C) A pathogen makes more than one antigen.

D) A lymphocyte has receptors for multiple different antigens.

E) A liver cell makes one class of MHC molecule.

 

D) A lymphocyte has receptors for multiple different antigens.

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98) Which of the following should be the same in identical twins?

A) the set of antibodies produced

B) the set of MHC molecules produced

C) the set of T cell antigen receptors produced

D) the susceptibility to a particular virus

E) the set of immune cells eliminated as self-reactive

 

B) the set of MHC molecules produced

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99) Vaccination increases the number of

A) different receptors that recognize a pathogen.

B) lymphocytes with receptors that can bind to the pathogen.

C) epitopes that the immune system can recognize.

D) macrophages specific for a pathogen.

E) MHC molecules that can present an antigen.

 

B) lymphocytes with receptors that can bind to the pathogen.