Endocrine and nervous systems and nervous systems… · Web viewendocrine system Jan 96,8 Which sequence correctly shows the path of sound transmission in the ear? Tympanic membrane

Endocrine and Nervous Systems

Jan 96,11. Which gland produces a hormone that directly increases blood supply to skeletal muscles and increases

the rate of contraction of heart muscle?

A. PancreasB. Adrenal glandC. Thyroid gland D. Pituitary gland

Jan 96,22. Which sequence illustrates a mechanism used by the body to control the blood glucose level?

A. Blood glucose increases release of glucagon increases conversion of glycogen into glucose decreases blood glucose decreases

B. Blood glucose decreases release of glucagon decreases conversion of glycogen into glucose decreases blood glucose increases

C. Blood glucose increases release of insulin increases conversion of glucose into glycogen increases blood glucose decreases

D. Blood glucose decreases release of insulin decreases conversion of glucose into glycogen increases blood glucose increases

Jan 96,3Use the following information to answer the next question

Diabetes insipidus is a disorder of the posterior lobe of the pituitary gland or hypothalamus resulting in decreased secretion of a specific hormone. This disorder is characterized by the excretion of large volumes of urine and subsequent dehydration and thirst.

A person with dibetes insipidus can be treated by inhaling a spray containing the hormone that is deficient. The spray is inhaled several times a day.

3. The inhaled spray would likely contain

A. insulinB. glucagonC. aldosteroneD. antidiuretic hormone

Jan 96, 4Use the following information to answer the next two questions

When the Chernobyl nuclear reactor in Ukraine melted down, clouds of radioactive material including iodine, were released into the atmosphere. Iodine is actively absorbed by a certain gland in the body. Scientists were worried that the radioactive iodine would cause tumors in this gland. In an attempt to avoid this problem, people who lived near the reactor were given large doses of non-radioactive iodine.

4. How would the ingestion large doses of non-radioactive iodine reduce a person’s chances of getting a tumor in a particular gland?

A. The pituitary would become saturated with non-radioactive iodine and this would limit the absorption of radioactive iodine

B. The thyroid would become saturated with non-radioactive iodine and this would limit the absorption of radioactive iodine

C. Increased levels of iodine would stimulate hormonal production by the pituitary and limit tumor formation

D. Increased levels of iodine would stimulate hormonal production by the thyroid and limit tumor formation

Jan 96, 55. If a tumor caused increased secretion of thyroxine, which symptoms would likely be experienced by an

affected person?

A. Increased body temperature and increased metabolic rateB. Increased body temperature and decreased metabolic rateC. Decreased body temperature and increased metabolic rateD. Decreased body temperature and decreased metabolic rate

Jan 96, 66. The pituitary hormone ACTH regulates the production of aldosterone by the cortex of the adrenal

glands. A severe drop in ACTH levels would likely result in

A. decreased sodium ion retention and increased water loss because aldosterone levels would rise

B. decreased sodium ion retention and increased water loss because aldosterone levels would drop

C. increased sodium ion retention and increased water retention because aldosterone levels would rise

D. increased sodium ion retention and increased water retention because aldosterone levels would drop

Jan 96,77. Sensory and motor neurons of the peripheral nervous system transmit impulses between muscles and

the

A. parasympathetic nervous systemB. sympathetic nervous systemC. central nervous systemD. endocrine system

Jan 96,88. Which sequence correctly shows the path of sound transmission in the ear?

A. Tympanic membrane eustachian tube semicircular canals cochleaB. Tympanic membrane semicircular canals eustachian tube cochleaC. Auditory canal ossicles tympanic membrane organ of CortiD. Auditory canal tympanic membrane ossicles organ of Corti

Jan 96,99. A person with a vitamin A deficiency may have night blindness. The glare from the headlights of an

approaching car will temporarily reduce that person’s visual capacity. The primary structures associated with this change are the

A. cornea and lensB. retina and rod cellsC. fovea and blind spotD. choroid and cone cells

Jan 96,1010. A person who occasionally experienced paralysis was examined and found to have very low levels of

potassium in the blood and other tissues. The paralysis likely resulted because of the inability of

A. capillaries to provide adequate blood flowB. axon terminals to break down acetylcholineC. neurons to repolarize during the refractory periodD. neurons to remove acetylcholine from the synapse

Jan 96,11

Use the following information to answer the next three questions

More than 4000 Gulf War veterans complain of illness (Gulf War Syndrome). The veterans’ symptoms include joint pain, shortness of breath, attention and memory problems, and chronic fatigue. During the war, most of the veterans took anti-nerve-gas pills. These pills contain pyridostigmine bromide, a drug that inhibits cholinesterase.

Pyridostigmine bromide is also used to treat patients with myasthenia gravis, an inherited disorder characterized by weakness of skeletal muscles.

11. The role of cholinesterase in neural transmission is to

A. increase the rate of nerve impulse transmissionB. promote the breakdown of a neurotransmitterC. increase the sensitivity of neural membranesD. promote the synthesis of a neurotransmitter

Jan 96, 1212. Considering that the symptoms of Gulf War Syndrome include attention and memory problems, it is

likely that pyridostigmine bromide has an effect on the

A. cerebrumB. cerebellumC. hypothalamus

D. medulla oblongata

Jan 96, 1313. In myasthenia gravis, a malfunction of neuromuscular synapses occurs. The information presented

above indicates that the muscular weakness associated with this disorder occurs because

A. axons secrete excess acetylcholineB. axons secrete insufficient acetylcholineC. of increased permeability of membranes to sodium ionsD. of decreased permeability of membranes to potassium ions


Scientists had long assumed that the brain could not produce new cells. However, two researches at the University of Calgary have successfully produced new brain tissue by using a unspecialized brain cell known as a stem cell. This stem cell acts as a “mother” cell to produce healthy brain tissue, in vitro.

14. Before this research, the assumption that brain cells could not regenerate was based upon which characteristic of axons?

A. Axons of the peripheral nervous system are surrounded by a neurilemmaB. Axons of the central nervous system are surrounded by a neurilemmaC. Axons of the peripheral nervous system lack a neurilemmaD. Axons of the central nervous system lack a neurilemma


Parkinson’s disease destroys certain neurons in the brain. One treatment for Parkinson’s disease is to transplant fetal brain tissue into a patient to replace neurons destroyed by the disease.

15. Which is a likely reason why fetal brain tissue, rather than brain tissue from an adult donor, is used to treat Parkinson’s disease?

A. Fetal neurons can undergo meiosis but adult neurons cannotB. Fetal neurons can undergo mitosis but adult neurons cannotC. Adult neurons are more complex than fetal neuronsD. Adult neurons are much larger than fetal neurons

Jun 96,1Use the following information to answer the next question

Multiple sclerosis (MS) is a disorder that causes the destruction of myelin sheaths surrounding neurons. People with MS display many symptoms, including slurred speech, double vision, and poor muscle coordination.

16. What is the direct effect of MS on nerve impulse transmission?

A. Dendrites cannot be stimulated by acetylcholine, therefore impulses are not generated in neurons.

B. Axons cannot secrete acetylcholine, therefore impulses are not able to travel across synapses.

C. The threshold level of stimulation for neurons is greater than normal.D. The movement of impulses along neurons is slower than normal.


Alzheimer’s disease is associated with the deterioration of memory and mental capacity due to decreased production of acetylcholine and loss of up to three-quarters of the neurons in parts of the brain.

17. Which phase of impulse transmission would be lacking in a person with Alzheimer’s disease?

A. Restoration of polarity in neuronsB. Excitation of postsynaptic neuronsC. Maintenance of resting potentials in neuronsD. Active transport of sodium and potassium in neurons


18. The voltage polarity is positive when

A. the neuron is restingB. an impulse is being transmittedC. an impulse dies out before reaching the axonD. the neuron has a high concentration of K+ ions

Jun 96, 4Use the following information to answer the next two questions

The tips of fingers are sensitive enough to discriminate raised points on a surface, as well as the locations of these points. Knowing this, in the 19th century Louis Braille invented the Braille system of reading for the blind. Each letter of a language alphabet is represented by up to six raised dots. A blind person who has learned the Braille system can read up to 50 words a minute.

17. Would a person preparing Braille script have to know if the blind reader was left- or right-handed, and thus change the order of the script accordingly?

A. No, because the sensations from both the right and left hand are carried by the spinal cord into the same hemisphere of the cerebrum

B. No, because the sensations received separately by the left and right cerebral hemispheres from the right and left hands are integrated before hey are interpreted into language

C. Yes, because the sensations from the right and left hands are carried to the left and right cerebral hemispheres respectively, and therefore the information is interpreted reverse order.

D. Yes, because the movements of the right and left hands are initiated by opposite sides of the cerebral cortex.

Jun 96,518. This sentence can be read using the eyes, but it could also be read using the fingertips if the sentence

was printed in Braille. This fact illustrates that

A. the brain can form the same meaning from different sensationsB. nerve impulses initiated by touch are identical to the nerve impulses initiated by sightC. receptors for touch and receptors for sight respond to the same environmental stimuliD. the lobe of the brain that receives sensations from the eyes is the same as the lobe that

receives sensations from the fingers

Jun 96,619. Which is a correct description of some sensory receptors in the eye?

A. Rods are concentrated in the fovea of the retina and function well in dim lightB. Cones are concentrated near the periphery of the retina and function well in dim lightC. Cones are concentrated in the fovea of the retina and function to detect coloursD. Rods are concentrated near the periphery of the retina and function to detect colours

Jun 96,7

Use the following information to answer the next question.

20. The detection of rotation of the head and the equalization of air pressure between the external environment and the middle ear are, respectively, functions of structures

A. 1 and 3B. 1 and 4C. 2 and 3D. 2 and 4

Jun 96,821. In humans, ADH and oxytocin can have similar effects. Therefore, a correct inference is that an

increase in the concentration of ADH in the blood may result in

A. increased urine volumeB. decrease metabolic rateC. increased contraction of uterine muscleD. decreased release of milk from the breasts

Jun 96,9


Vegetables such as cabbage, rutabaga, and turnips contain goitrin, a substance that inhibits iodine uptake by the body.

22. A person with a diet high in vegetables containing goitrin may gain weight fairly rapidly. A possible explanation for this weight would be

A. increased protein metabolismB. decreased blood sugar levelsC. increased glycogen releaseD. decreased metabolic rate

Jun 96,1023. The function of which gland would be most affected by goitrin?

A. Anterior pituitaryB. Adrenal cortexC. PancreasD. Thyroid

Jun 96,1124. An increase in goitrin consumption would likely cause a person to experience increased

A. fatigueB. heart rateC. breathing rateD. urine production

Jun 97,1

Use the following information to answer the next two questions

25. This neuron transmits an impulse from a receptor to the central nervous system; therefore, it is

A. a motor neuronB. a sensory neuronC. an autonomic neuronD. an association neuron

Jun 97,1Numerical Response1. In the diagrammed neuron, which numbers represent segments of the axon that are, respectively,

polarized, repolarized, and depolarized, during normal neural impulse conduction?

(Record your three-digit answer in the numerical-response section of the answer sheet.)

Answer: _____________ _____________ ______________ polarized repolarized depolarized

Jun 97,2


Numerical Response2. Identify the sequence of events that would occur when a signal crosses the synapse.

(Record your four-digit answer in the numerical-response section of the answer sheet.)

Answer: ___________

Jun 97,2

Use the additional information to answer the next question

Serotonin is neurotransmitter found in the brain. Some studies show that too little serotonin may cause depression and lead to a tendency to behave impulsively.

- from The Edmonton Journal

26. Excitatory neurotransmitters like serotonin

A. hyperpolarize a postsynaptic neural membraneB. block the postsynaptic membrane’s receptor sitesC. increase the permeability of postsynaptic membranes to sodiumD. decrease the permeability of postsynaptic membranes to sodium

1. Attachment of neurotransmitters to receptor molecules2. Diffusion of neurotransmitters across the synapse3. Destruction of the neurotransmitter by an enzyme4. Exocytosis of the neurotransmitter

Jun 97,3

Use the following diagram to answer the next question

27. Which structure acts as a lever to mechanically amplify sound vibrations?

A. Structure 1B. Structure 2C. Structure 3D. Structure 4

Jun 97,428. A person outside the gravitational field of Earth experiences disruption of normal functions of the

inner ear. The region of the brain processing the disruption and the ability affected by this disruption are, respectively, the

A. cerebellum and the ability to walk a straight lineB. cerebrum and the ability to write legiblyC. cerebellum and the ability to hearD. cerebrum and the ability to speak

Jun 97,5

Use the following information to answer the next question

29. For a person to experience sight, neural transmissions from structure X must reach which lobe of the cerebrum?

A. The frontal lobeB. The parietal lobeC. The occipital lobeD. The temporal lobe

Jun 97,630. After having a stroke, a person finds that he cannot contract muscles in his right arm and that he suffers

from speech impairment. The person probably has brain damage in the

A. left side of the cerebrumB. right side of the cerebrumC. left side of the cerebellumD. right side of the cerebellum

Jun 97,7


Polygraphs (lie detectors) monitor some changes in some activities of the nervous system. In theory, an emotionally stressful situation like telling lies will increase perspiration, increase breathing and heart rates, and cause slight dilation of pupils. However, polygraphs cannot exclusively differentiate between telling lies and other stressful situations.

31. The physiological changes that are associated with telling lies are responses produced by impulses coming from

A. motor nerves of the somatic nervous systemB. sensory nerves of the somatic nervous systemC. sympathetic nerves of the autonomic nervous system

D. parasympathetic nerves of the autonomic nervous system

Jun 97,832. Emotionally stressful situations may affect more than one system of the body. Another possible

response produced by telling lies would be

A. decrease secretion of ADHB. increased secretion of insulinC. decreased secretion of glucagonD. increased secretion of epinephrine

Jun 97,9Use the following information to answer the next two questions

On April 26, 1986, a major accident occurred at a nuclear generating station in Chernobyl. The nuclear explosion dispersed several tons of radioactive iodine, cesium, uranium, and other elements five kilometers into the air.

Radioactivity is extremely damaging to living cells.- from Biosphere 2000: Protecting Our Global Environment

33. As soon as people in Europe realized there had been a nuclear accident, they rushed to buy iodine tablets. What reason would people have for consuming large quantities of iodine?

A. So that iodine form the tablets, instead of the radioactive iodine, would accumulate in the thyroid

B. Because iodine, by negative feedback, blocks the formation of TSH, therefore protecting the thyroid from radioactivity

C. Because iodine inhibits cell division, thereby reducing the amount of cellular damage occurring during exposure to radiation

D. So that iodine could accumulate in the hypothalamus and block communication between the nervous and endocrine systems

Jun 97,1034. Which symptoms would be expected among people who did not take iodine tablets?

A. Pancreatic dysfunction and insufficient insulin productionB. Metabolic dysfunction resulting in fatigue and weight gainC. Increased ACTH secretion and puffiness of face, chest, and abdomenD. Pituitary dysfunction resulting in increased HGH secretion and thus giantism

Jun 97,11

Use the following diagram to answer the next question

35. Hormones X and Y, respectively, are

A. insulin and glucagonB. glucagon and insulinC. insulin and epinephrineD. epinephrine and insulin

Jun 97, 12


36. If Gland 1 is the pituitary gland, the row that identifies Hormone1, Gland 2, and Hormone 2 is

Row Hormone 1 Gland 2 Hormone 2A. FSH Testes testosteroneB. TSH Thyroid thyroxineC. FSH Ovaries progesterone

Control of the Secretion of Hormone 1 and Hormone 2

D. ADH kidney aldosterone


37. A steroid hormone likely alters cell function when a hormone-receptor complex

A. produces enzymes necessary for protein synthesisB. enables DNA to leave the nucleus to synthesize proteinsC. translates mRNA required for protein synthesis in the nucleusD. activated genes responsible for the synthesis of particular proteins

A steroid hormone secreted from a gland attaches to a binding protein and travels in the blood plasma to a target organ. The hormone is released from the binding protein, enters a target cell, and binds to a specific receptor molecule.

Jan 98,1


38. Which of the following statements is true of the threshold potential?

A. It is the same electrical potential for all neuronsB. It is the depolarization required to generate an action potentialC. It determines the time it takes for an action potential to be completedD. It determines the time it takes for an impulse to travel along the axon

Jan 98,239. Relative to inside of a neuron, the extracellular fluid immediately outside a resting neuron’s cell

membrane is

A. positive and the sodium ion concentration is lessB. negative and the sodium ion concentration is lessC. positive and the sodium ion concentration is greaterD. negative and the sodium ion concentration is greater

While animals interact with their external environment, their nervous and endocrine systems maintain internal equilibrium. The study of organisms and of disease processes has helped extend our knowledge of these system.

Jan 98,1


Numerical Response3. An impulse arrives at an axon terminal that synapses with a muscle cell. Record the processes in the

order that they occur at the synapse


Answer: _____________

Jan 98,340. Certain chemicals inhibit cholinesterase at neuromuscular junctions. The resulting muscular spasms

occur because of the

A. depletion of cholinesterase in the presynaptic neuronB. depletion of acetylcholine in the neuromuscular junctionC. accumulation of cholinesterase in the presynaptic neuronD. accumulation of acetylcholine in the neuromuscular junction

Jan 98,4


41. The division of the nervous system that was damaged in these rats is the

A. central nervous systemB. somatic nervous systemC. sympathetic nervous systemD. parasympathetic nervous system

Processes That Occur at a Neuromuscular Junction(A Type of Synapse)

1 Muscle fibres contract when sodium gates open allowing sodium ions to diffuse into the muscle cytoplasm

2 Acetylcholine is released from the axon terminal3 Acetylcholine binds to the receptors on the muscle cell4 Cholinesterase breaks down acetylcholine, and the sodium gates close

-from Guyton

Twenty-two once-paralyzed rats can now move their hind legs and even take awkward steps. Their damaged spinal cords have been partially repaired by surgically grafting nerve fibers from another part of their bodies to the damaged area.

-from Flam

Jan 98,5


42. Neurotransmitters are released from

A. site XB. site ZC. sites X and YD. sites X and Z

Jan 98,643. If neurons I and II are interneurons, neuron III cannot be a

A. parasympathetic neuronB. sympathetic neuronC. sensory neuronD. motor neuron

Jan 98,744. In a typical reflex arc, neuron III would be part of the

A. effectorB. receptorC. motor pathwayD. sensory pathway

Jan 98,845. When adaptation of the eye occurs to view objects in a dark room

A. the pupil increases in size and the rods become activeB. the pupil decreases in size and the rods become activeC. the pupil increases in size and the cones become activeD. the pupil decreases in size and the cones become active

Jan 98,9


46. Which parts of the ear contain these sensory hair cells?

A. Auditory nerve and cochleaB. Eardrum and auditory nerveC. Eustachian tube and eardrumD. Cochlea and semicircular canals

Jan 98,10


47. Normally, inhibition of the pituitary gland would occur if the secretion of hormone X

A. increased, causing a decrease in the secretion of hormone YB. decreased, causing a decrease in the secretion of hormone YC. increased, causing an increase in the secretion of hormone YD. decreased, causing an increase in the secretion of hormone Y

Jan 98,11


48. Another stress hormone whose functions mimic those of the sympathetic nervous system is

A. HCGB. insulinC. estrogenD. norepinephrine

Sensory hair cells in the inner ear can be damaged by excessive noise or certain drugs. This may cause deafness or balance disorders. Research suggests that these cells have the ability to regenerate. In one study, the damaged inner ear tissue of guinea pigs was cultured in a dish. The damaged tissue produced new sensory hair cells.

- from Gutin

Stressful situations trigger the release of hormones such as cortisol. Recent studies have found that some forms of depression cause a similar hormonal response that lasts much longer than the normal stress response. This unregulated release of stress hormones may result in reduced appetite, an unresponsive immune system, inadequate tissue repair, and insomnia.

Jan 98,12

Use the following additional information to answer the next question

49. A logical interpretation of the graph is that the

A. secretion of cortisol is inhibited by increased ACTHB. secretion of cortisol is doubled if the secretion of ACTH is doubledC. adrenal glands respond more quickly to small amounts of ACTH than to large amounts of

ACTHD. adrenal glands respond to large amounts of ACTH by having a maximum cortisol

secretion rate


50. Hormone “X” was most likely

A. ADHB. ACTHC. oxytocinD. aldosterone

In 1947, E. B. Verney published the results of a series of experiments that he had conducted on a number of dogs. He found that if he injected a concentrated salt solution into the bloodstream, hypothalamus, and ventricles of the brain, hormone “X” was released in large amounts

A dog with a malfunctioning pituitary gland received injections of ACTH. Data were collected after the dog’s injections.

Rate of Cortisol Secretion After the Injection of Varying Amounts of ACTH

Jan 98,1451. The endocrine function of the pancreas was studied in Canada using dogs as experimental animals. The

pancreatic cells with an endocrine function are

A. islet cellsB. blood cellsC. Sertoli cellsD. interstitial cells

Jan 98,15Use the following information to answer the next two questions

52. BST could probably be obtained naturally from which gland in a cow?

A. ThyroidB. AdrenalC. PituitaryD. Pnacreatic

Jan 98,1653. In a cow’s mammary gland, BST is most similar in its effect to

A. estrogenB. oxytocinC. prolactinD. progesterone

Jan 98,1754. In humans, when iodine levels are adequate, abnormally high TSH secretion would likely result in

A. nervousness and weight gainB. nervousness and weight lossC. sleepiness and weight gainD. sleepiness and weight loss

Bovine somatotropin (BST) is a growth hormone that has been produced using biotechnology since 1970. BST increases milk production by 10% to 20% when injected into milk-producing cows. BST increases nutrient absorption from the bloodstream into the cow’s mammary gland.

-from Harpp and Joseph

Jan 98,18


55. Males exposed to high levels of these estrogen-mimicking chemicals could experience

A. development of breastsB. development of ovariesC. increased growth of musclesD. increased growth of facial hair


56. It appears that the hormone estrogen has an effect on the

A. cerebrumB. cerebellumC. hypothalamusD. medulla oblongata


57. Assume that the biker’s nervous system was not injured and that the biker’s body responded in a normal way to the gentle tap. The neurological pathway that was followed when this response was elicited was

A. receptor, sensory neuron, interneuron, motor neuron, effectorB. effector, sensory neuron, interneuron, motor neuron, receptorC. receptor, motor neuron, interneuron, sensory neuron, effectorD. effector, motor neuron, interneuron, sensory neuron, receptor

Several studies have indicated that sperm counts in humans have declined over the past 25 years. Increased levels of chemicals in the environment that mimic estrogen have been found in substances ranging from detergents to plastic wrappers. These chemicals are a suspected cause of the decline in sperm counts.

-from Stainsby

The symptoms of Alzheimer’s disease gradually appear as affected individuals age. One symptom of Alzheimer’s disease is a loss of memory. Studies have shown that the administration of the hormone estrogen to female patients with Alzheimer’s disease dramatically improved their memory.

-from Calgary Herald, 1996

After a head injury, a mountain biker was assessed by a doctor. One of the tests the doctor did was to gently tap just below her kneecap. Also, he shone a light into each of her eyes and made observations. In both tests, he was trying to quickly rule out any neurological damage.


58. Paralysis of muscles below the site of a spinal cord injury is often permanent because neurons in the grey matter of the spinal cord all lack a

A. nucleusB. dendriteC. cell bodyD. neurilemma


59. The resting axon is labeled

A. WB. XC. YD. Z

Diving improperly into a swimming pool or into a lake may cause injuries that damage the spinal cord. the victims of these injuries often suffer loss of the sensation of heat and touch on the skin and paralysis of muscles below the site of the injury.


60. Destruction of the synaptic vesicles of Neuron 1 will

A. block the nerve impulse at WB. cause X to be constantly stimulatedC. prevent depolarizations from occurring at YD. result in the action of cholinesterase in Neuron 2

Jun 98,1


Numerical Response4. Assume that the ear structure of bats is similar to that of humans. What pathway would these “chirp”

sound waves take through the ear to be detected by the temporal lobe?

Structures of the Ear1 Semicircular canals2 Organ of Corti3 Eustachian tube4 Tympanic membrane5 Auditory canal6 Ossicles


Answer: _____ _____ _____ _____

Bats emit a high-frequency “chirp” as they fly. They listen for the reflection of this sound off of moths, their food, by interpreting the time it takes for the sound to return, they can effectively catch moths, even in total darkness.

- from Curtis, 1983


61. When glaucoma occurs, the part of cerebrum that does not receive visual information is the

A. frontal lobeB. parietal lobeC. occipital lobeD. temporal lobe

Jun 98,7Use the additional information to answer the next question

62. Blindness due to optic nerve damage and blindness due to retinal detachment are similar because they both

A. involve damaged receptorsB. affect blood flow to the eyeC. involve damaged occipital lobesD. affect nerve impulse transmission to the brain

Retinal detachment is a disorder of the eye that is closely related to aging. It may also be the result of a direct injury to the eye. In this disorder, sections of the retina become separated from the layer behind it. Fluid fills the resulting spaces.

-from Taber, 1989

Jun 98,8Use the following information to answer the next four questions

63. The gland that is directly stimulated by the nervous system to secrete hormones is the structure labeled

A. 2B. 3C. 4D. 5

Jun 98,964. The structure that produces only hormones is labeled

A. 1B. 2C. 5D. 6

Jun 98,1065. A target organ for aldosterone is the structure labeled

A. 3B. 5C. 6D. 7

Jun 98,1166. A patient is suffering from weight gain, sluggishness, and dry skin. The patient is injected with a

tracer, radioactive iodine, to identify the structure responsible for these symptoms. The tracer would most likely accumulate in the structure labeled

A. 1B. 2C. 4D. 7

Jun 98,1267. When the hypothalamus fails to produce ADH, the physiological effect that is most likely is

A. muscle spasmsB. loss of memoryC. decreased breathing rateD. increased urine production

Jun 98,13Use the following information to answer the next question.

68. If the physiological factor influencing this negative feedback loop were the metabolic rate, then 1, 2, and 3, respectively, would be the

A. hypothalamus, pituitary, and thyroidB. thyroid, hypothalamus, and pituitaryC. pituitary, thyroid, and hypothalamusD. pituitary, hypothalamus, and thyroid

Jun 98,1469. The response to increased glucose levels in the blood is the conversion of glucose to glycogen. This

response is the result of the secretion of

A. insulin by the adrenal medullaB. glucagon by the adrenal medullaC. insulin by the islets of LangerhansD. glucagon by the islets of Langerhans

Jun 98,1570. While playing a vigorous game of basketball, a person’s overall rate of metabolism increases. Which

two hormone levels rise so that blood glucose levels meet the needs of the increased metabolic rate?

A. Cortisol and ADHB. Steroids and HGHC. Insulin and acetylcholineD. Epinephrine and glucagon


71. In humans, HGH directly stimulates the

A. gonadsB. adrenal glandsC. muscles and peripheral nervesD. long bones and skeletal muscles

Jun 98,1772. Why might nondisjunction produce more serious effects on the population if it were present in gametes

produced by a female rather than in gametes produced by a male?

A. An egg (ovum) is larger than a spermB. Fewer eggs (ova) are produced than spermC. An egg mother cell (oogonium) divides twice but a sperm mother cell (spermatogonium)

divides only onceD. An egg mother cell (oogonium) divides equally but a sperm mother cell

(spermatogonium) divides unequally

HGH is a protein. Biosynthetic HGH is used in the treatment of Turner syndrome, a disorder occurring in females as a result of nondisjunction; the sex chromosome complement is XO instead of the normal XX. Untreated females with Turner syndrome grow only to the height of an average ten-year-old.

-From Leger, 1994

Jun 99,1Use the following information to answer the first three questions

73. Persons affected by panic attacks appear to be “sensitive” to CCK. This hypothesis would be supported if such persons were found to have

A. low levels of CCKB. impaired production of CCKC. CCK inhibitors at these synapsesD. Excess postsynaptic receptors for CCK

Jun 99,274. After mRNA has been produced, the production of CCK is the result of

A. translationB. replicationC. transcriptionD. recombination

Jun 99,375. Injections of CCK produce responses similar to those produced by the stimulation of

A. interneuronsB. sensory neuronsC. sympathetic motor neuronsD. parasympathetic motor neurons

“It begins in your gut and quickly spreads to your heart and head. Your confidence is swept away with dark foreboding as your heart races and your stomach becomes nauseous.”

This description was given by a person experiencing a “panic attack” induced by the injection of cholecystokinin (CCK). CCK is a molecule with different functions in different parts of the body. In the brain, it acts as a neurotransmitter that normally regulates memory and recall. It also arouses the emotional and motivational regions of the brain. A gene that encodes CCK has been located.

-from Hall, 1996

Jun 99,4Use the following information to answer the next three questions

76. For the neurotransmitters dopamine and acetylcholine, the releasing sites and the receptor sites are, respectivly,

A. cell bodies and dendritesB. dendrites and Schwann cellsC. axon terminals and dendritesD. axon terminals and Schwann cells

Jun 99,577. What role do both dopamine and acetylcholine have when they function as excitatory

neurotransmitters?

A. They make the presynaptic membrane more permeable to K+ ionsB. They make the presynaptic membrane more permeable to Na+ ionsC. They make the postsynaptic membrane more permeable to K+ ionsD. They make the postsynaptic membrane more permeable to Na+ ions

Jun 99,6Use the following additional information to answer the next question

78. Would it be reasonable to use NGF to regenerate neurons in which nuclei had been destroyed?

A. Yes, because not all cells require a nucleus to functionB. Yes, because organelles other than the nucleus cause growthC. No, because the nucleus controls protein synthesis and homeostasisD. No, because without the nucleus to actively transport ions, the cell would die

Two symptoms of Parkinson’s disease are lack of muscular coordination and tremors, both caused by inadequate amounts of dopamine. Symptoms of Alzheimer’s disease include the deterioration of memory and mental abilities, possibly caused by a decrease in acetylcholine production.

Dopamine and acetylcholine are excitatory neurotransmitters in various parts of the brain.

Damage to neurons in different parts of the brain appears to cause Parkinson’s and Alzheimer’s diseases.

Nerve growth factor (NGF), a chemical produced by peripheral nerves, promotes axon regeneration. Studies show that neurons of the CNS are capable of regeneration when NGF is produced by genetically engineered cells that are transplanted in the CNS.

- from Greene, 1993

Jun 99,779. Which of the following situations illustrates that simple reflexes can be controlled through learned

behaviour or conscious effort?

A. A student cries “ouch” after pulling his hand away from a sharp pinB. A knee jerk occurs when the patellar ligament below the kneecap is tappedC. While clenching a textbook against his chest, a student has an exaggerated knee jerkD. Even though she is burned, a mother does not drop a pot of boiling water when her child

is standing at her side


80. After studying the data, a student stated, “From age 10 to age 60, the eye has an ever-increasing ability to focus on nearby objects.” This statement represents

A. a restatement of the dataB. a theory supported by the dataC. an interpretation supported by the dataD. an interpretation contradicted by the data

Age and Eye Accommodation

Age in Years Near Point Accommodation* (cm)

10 7.5

20 10.0

30 11.5

40 17.2

50 65.9

60 90.0

*The shortest distance between the eye and an object where focus of the object is achieved.

-from Aschmidt and Thews, 1983


81. Which of the following statements presents a valid interpretation of the information on the graph?

A. A temperature of 5oC is less painful than a temperature of 50oCB. A sensation of coolness is interpreted only when two types of receptors are stimulatedC. The threshold level of stimulation is higher for temperature receptors than it is for pain

receptorsD. Temperature sensations are determined by the number of impulses per second and the

specific type of receptors


82. The areas of the brain affected by mercury poisoning as indicated by the above symptoms are, as respectively, the

A. cerebrum and medullaB. cerebellum and cerebrumC. cerebrum and cerebellumD. hypothalamus and cerebellum


83. Mercury compounds most likely affect the level of the hormone

A. LHB. FSHC. ADHD. ACTH


84. Exposure to mercury compounds during embryological development would most likely disrupt the

A. production of amniotic fluidB. development of the neural tubeC. production of ovarian hormonesD. development of the umbilical cord

Mercury poisoning causes neurological damage, which leads to a deterioration of short-term memory and an inability to coordinate muscle movements.

Mercury poisoning also affects the pituitary gland in such a way that frequent urination results.

Certain mercury compounds are able to cross the placenta and thereby affect embryological development.

-from Hedegard, 1993


85. If huperzine A were present in synapses between motor neurons and muscles, it would

A. prevent the breakdown of acetylcholineB. prevent the contraction of skeletal musclesC. cause the release of sodium ions from axon terminalsD. cause the secretion of acetylcholine from axon terminals


86. Which hormone is released as a direct result of sympathetic motor neuron stimulation?

A. HGHB. ThyroxineC. AldosteroneD. Epinephrine

For hundreds of years, Chinese folk doctors have known an intriguing but mysterious fact. Drinking herbal tea brewed with a type of club moss (Huperzia serrata) can improve a person’s memory.

About ten years ago, researchers at the Shanghai Institute of Materia Medica isolated a compound from the tea that is a strong inhibitor of cholinesterase. The compound, called huperzine A, and its effect on acetylcholine are the subjects of intense research. Researchers hope to use huperzine A as an over-the-counter drug and as a potential medication for Alzheimer’s disease.

-from Cheng, Ren and Tang, 1996

During stressful experiences, interactions between the nervous and endocrine systems prepare the body to defend itself or to handle injury.

Jun 99,15Use the following additional information to answer the next two questions

87. If blood glucose levels change, the pancreas will

A. stop hormone secretions because the target cells are not workingB. produce a more active form of the hormone that stimulates the target cellsC. cause other endocrine glands to secrete hormones that stimulate the target cellsD. increase the secretion of the appropriate hormone that stimulates the target cells

Jun 99,1688. The names of hormones X and Y are, respectively,

A. insulin and glucagonB. glucagon and insulinC. glycogen and insulinD. insulin and glycogen

Jan 00,1Use the following information to answer the first two questions

89. The part of the brain that is directly responsible for the recall of previously learned words is the

A. cerebrumB. cerebellumC. pituitary glandD. medulla oblongata

Jan 00,290. The part of the brain that controls the unconscious rate of breathing is the

A. cerebrumB. cerebellumC. pituitary glandD. medulla oblongata


91. Nerve impulse transmission continues along the nerve cell membrane as

A. a wave of depolarizationB. a negative feedback loopC. a diffusing wave of summationD. the active transport of an electrical potential

Jan 00,492. The part of the ear directly responsible for stimulating the nerve endings that transmit sound impulses

from the ear to the brain is the

A. cochleaB. eardrumC. Eustachian tubeD. semicircular canal

A group of psychologists wondered if inhaling pure oxygen could enhance a person’s mental capacity. They tested forty-five students.

These students breathed through a facemask for one minute. They were either given pure oxygen or normal air, but they did not know which. Those receiving pure oxygen could recall twice as many words as those receiving normal air.

-from Mihill, 1996

Movement of hair cells in normal ears opens tiny pores called ion channels in the nerve cell membrane. This process begins impulse transmission along the auditory nerve.


93. If an eagle’s brain were similar in structure to a human brain, impulses that begin in the retina of the eagle’s eye would travel first to the

A. frontal lobeB. parietal lobeC. occipital lobeD. temporal lobe

Jan 00,694. Strong near and far accommodation in the eye require

A. small blind spotsB. a large number of rodsC. a large number of conesD. highly developed ciliary muscles

Jan 00,1Use the following diagram to answer the next question.

Numerical Response5. Identify the structure, as numbered above that performs each of the functions given below.

Structure: __________ __________ __________ __________ Function: Transmits impulses Receives sensory Carries out Transmits impulses

to the central stimulation instructions from from the centralnervous system the central nervous nervous system to

system; is a the effectormuscle

(Record your four-digit answer in the numerical-response section on the answer sheet.)

Many predatory birds such as eagles have two foveae in each eye. The fovea in predatory birds is similar in structure and function to the fovea in humans. In addition, these birds have strong powers of near and far accommodation.

-from Curtis, 1983

Jan 00,795. Jogging will cause heart rate to change because of

A. increased sympathetic and decreased parasympathetic impulsesB. decreased sympathetic and increased parasympathetic impulsesC. increased sympathetic and decreased central nervous system impulsesD. decreased sympathetic and increased central nervous system impulses

Jan 00,896. Damage to which of the following endocrine glands would most affect the reaction of the body to an

emergency that stimulates the sympathetic nervous system?

A. thyroid glandB. adrenal glandC. anterior pituitary glandD. posterior pituitary gland


97. In a human female, where are the target cells for ADH and oxytocin?

A. in the kidney tubules and ovariesB. in the Bowman’s capsule and the ovariesC. in the kidney tubules and uterine musclesD. in the Bowman’s capsule and the uterine muscles

Oxytocin and ADH are synthesized by neurosecretory cells in the hypothalamus. These hormones are stored in the posterior pituitary. They can then be released into the bloodstream where they circulate to target cells.


98. In humans, high levels of GnRF cause the pituitary to release

A. LH and FSHB. LH and estrogenC. progesterone and FSHD. estrogen and progesterone


Numerical Response6. Identify the response, as numbered above, that would be stimulated by each of the hormones given

below.

Response: __________ __________ __________ ___________Hormone: STH (HGH) LH TSH FSH

(Record your four-digit answer in the numerical-response section on the answer sheet.)

Responses Stimulated by Hormones

1 Release of thyroxine 4 Development of follicle and sperm2 Development of bones and muscles 5 Ovulation and maintenance of the corpus luteum3 Water reabsorption by kidneys 6 Milk production


99. Which of the following conclusions can be made about these related diseases?

A. A person can easily contract syphilis in warm climatesB. The syphilis strain of Treponema may have mutated from the yaws strainC. Non-sexually transmitted diseases have developed from sexually transmitted diseasesD. Older people tend to suffer from yaws, and younger victims develop syphilis when

exposed to Treponema.

Jan 00,22Use the following additional information to answer the next question

100.The neurons damaged by syphilis are

A. interneuronsB. sensory neuronsC. somatic motor neuronsD. autonomic motor neurons

Yaws, bejel, and syphilis are three diseases known to be caused by strains of bacteria in the genus Treponema. Syphilis is a sexually transmitted disease, whereas yaws and bejel are not sexually transmitted. Studies of 800-year-old to 1,600-year-old skeletons from Florida, Equador, and New Mexico show that these people suffered from syphilis. Studies on 6,000-year-old skeletons from Illinois, Virginia, and Ohio show that these people suffered from yaws.

-from Zabludoff, 1996

The symptoms of untreated syphilis usually disappear within 12 weeks of the initial infection. However, new symptoms may appear many years later. These include damage to neurons of the central nervous system.

-from Zabludoff, 1996

Jun 00,1Use the following information to answer the first two questions

101.After riding the Tilt-A-Turn at an amusement park, people are often dizzy. Which of the structures numbered above is initially stimulated to cause the sensation of dizziness?

A. Structure 1B. Structure 2C. Structure 3D. Structure 5

Jun 00,2102.Which of the structures numbered above function together to convert sound waves to mechanical

vibrations, and then to amplify these vibrations?

A. Structures 6 and 1B. Structures 5 and 2C. Structures 6 and 3D. Structures 5 and 4

Jun 00,3Use the following information to answer the first three questions

103.Which of the following rows correlates possible observations about the accident victim with locations of nerve damage?

Row Possible ObservationsLocations of Nerve

DamageA. The man could not move his wrist and could not

feel sensations from his hand1 and 2

B. The man could move his wrist normally but could not feel sensations from his hand

1 and 4

C. The man could not move his wrist but could feel sensations from his hand

2 and 3

D. The man could move his wrist normally and could feel sensations in his hand

2 and 4

Jun 00,4104.If, following the accident, the man exhibited a marked changed in personality, the doctor would

suspect damage to the

A. medullaB. cerebrumC. cerebellumD. hypothalamus

A man was injured in an automobile accident. There appeared to be damage to his back, his arm, and his head.

A doctor examined the man, noted some symptoms, and hypothesized that nerve damage had occurred.


105.The structure that allows neurons of peripheral nerves to regenerate is the

A. axonB. dendriteC. neurilemmaD. node of Ranvier


106.According to the data table, which group of rats was most likely the control group?

A. IB. IIC. IIID. IV

Research has shown that although interneurons in the spinal cord make proteins that inhibit regeneration of damaged axons, peripheral nerve axons can regenerate.

A laboratory technician was asked to set up an experiment to determine the effect of thyroxine on metabolic rate. Four groups of adult male laboratory rats were used. Each group was placed in the same type of cage, which was designed to provide room for physical activity. Each of the four groups was given an adequate supply of water and one of the four diets listed below:

Diet W: rat chow, a preparation of rat food containing all essential nutrientsDiet X: rat chow containing a chemical that counteracts the effect of thyroxine in the bodyDiet Y: rat chow containing dried thyroid tissue, which contains thyroxineDiet Z: rat chow deficient in iodine

The technician was not aware of which diet she was feeding to each group of rats. The following data were obtained:

GroupAverage Initial Weight

(g)Average Final Weight After Two Weeks (g)

Final Average Oxygen Consumption(mL/kgmin)

I

II

III

IV

323

328

330

315

392

287

400

320

2.5

10.0

2.0

4.0

Jun 00,7107.The row below that correctly identifies two groups of laboratory rats and the diets they were most

probably fed is

Row Group Diet Group DietA. I Z II WB. I W IV XC. II Y III XD. III Z IV Y


108.The drugs numbered above that would act as competitive inhibitors to serotonin and the drugs that would slow down the rate of removal of serotonin from the synapse are, respectively,

A. I and IIIB. II and IC. II and IIID. III and IV

Jun 00,9109.If a person were suffering from clinical depression, which of the following drugs would not reduce the

symptoms of depression?

A. LSDB. ZoloftC. ClozapineD. Fenfluramine

Serotonin is a naturally occurring neurotransmitter that plays an important role in a person’s mood and emotions. A shortage of serotonin has been associated with phobias, schizophrenia, aggressive behaviour, depression, uncontrolled appetite, and migraine headaches. Synthetic drugs have been developed to enhance or hinder the performance of serotonin in the brain. Some of these drugs included:

I Prozac and Zoloft, which cause serotonin to remain in the brain for longer periods of time II Drugs, such as Clozapine, that prevent serotonin from binding to post-synaptic

membranesIII Diet drugs, such as Redux and Fenfluramine that stimulate nerve cells to release more

serotoninIV Hallucinogens, such as LSD and Ecstasy, that react directly with serotonin receptors to

produce the same effect as serotonin. -from Lemonick, 1997


110.Row Released from structure Found in theA. W axon terminalB. X dendriteC. Y axon terminalD. Z dendrite


111.Melatonin secretion decreases when light stimulates receptors found in the structure labeled

A. 1B. 2C. 3D. 4


112.Increased melatonin release due to decreased light exposure would reduce fertility in female mammals if it

A. caused an increase in the secretion of LHB. caused an increase in the secretion of FSHC. stimulated the release of hormones from the pituitaryD. prevented the release of gonadotropin-releasing hormones form the hypothalamus

Scientists have discovered that, in many mammals, light exposure effects schedules of reproduction. Decreased light exposure in early winter results in a decrease in fertility in these mammals.

-from Norman and Litwack, 1997

Many scientists believe that sleep cycles are influenced by the hormone melatonin. Two scientists have shown that the retinas in hamsters are involved in maintaining a 24-hour cycle. Their research shows that impulses sent from the retina to the brain after exposure to light influence the secretions of melatonin. Melatonin is normally produced in greater amounts at night when the eyes are exposed to less light. In humans, melatonin produces drowsiness.

Jun 00,13Use the following additional information to answer the next three questions

113.In this study, the manipulated variable, responding variable, and a possible fixed (controlled) variable are given in row

Row Manipulated Variable Responding Variable Fixed VariableA. amount of licking by

mother ratsamount of ACTH released in adult rats

rat’s cage size

B. amount of ACTH released in adult rats

amount of licking by mother rats

age of mother rats

C. amount of stress in environment

amount of ACTH released in adult rats

amount of licking by mother rats

D. amount of licking by mother rats

heart disease in adult rats

amount of ACTH released in adult rats


114.Humans, as well as rats, release ACTH in response to stress. The row below that identifies the gland that secretes ACTH and the target gland of ACTH in humans is

Row Secreting Gland Target GlandA. 1 2B. 1 3C. 2 4D. 2 5

Researchers have been studying the connection between maternal care and stress in rats. Those rats that received more licking and grooming as babies release lower levels of ACTH in response to stress as adults. In humans, high levels of stress hormones are linked to an increase in heart disease, diabetes, depression, and alcoholism.

-from Strauss, 1997

Jun 00,15115.When a person, or a rat, is exposed to stressful situation, the response of the nervous system is the

activation of the

A. sympathetic nervous system and the release of epinephrine by post-ganglionic fibresB. sympathetic nervous system and the release of acetylcholine by post-ganglionic fibresC. parasympathetic nervous system and the release of epinephrine by post-ganglionic fibresD. parasympathetic nervous system and the release of acetylcholine by post-ganglionic

fibres

Jan 01,1Use the following information to answer the first question

116.This sequence of events may be explained by the fact that the

A. threshold of the receptor has been so greatly exceeded that the neuron does not pass the message to the brain

B. neural impulse is so large that the brain is unable to interpret the signal because it is beyond the range of tolerance

C. neural processing occurred in the spinal cord first, which caused you to quickly remove your thumb from further damage

D. sensory receptors in the thumb were damaged by the blow and are unable to initiate a stimulus to the sensory nerve

Jan 01,2117.Stimulation of an individual’s sympathetic nervous system in response to imminent danger leads to all

of the following responses except

A. dilation of the pupils of the eyesB. constriction of the bronchioles of the lungsC. constriction of the arterioles of the intestinesD. dilation of the arterioles of the skeletal muscles

After accidentally hitting your thumb with a hammer, you immediately withdraw your hand. You do not feel pain for a short period of time.


118.The part of the motor neuron that may release acetylcholine is labelled

A. 1B. 2C. 3D. 4

Jan 01,4119.What would happen if acetylcholine was released at a synapse, but no cholinesterase was present?

A. The acetylcholine would fail to stimulate the postsynaptic neuronB. The acetylcholine would diffuse more rapidly across the synaptic cleftC. A single nerve impulse would be generated in the postsynaptic neuronD. The postsynaptic neuron would remain in a constant state of depolarization


119.Dopamine transmission is affected when dopamine transporters, which normally carry dopamine back to the cell that formed it, are occupied by cocaine. The effects of cocaine occur because dopamine

A. is produced in increased concentrationB. remains in the synapse in high concentrationC. levels drop rapidly as the molecules react with cocaineD. is transported very effectively to the postsynaptic neuron

The brain neurotransmitter dopamine is linked to the good feelings associated with actions such as receiving a friendly hug. When cocaine is present in synapses, it binds with dopamine transporters producing similar emotional effects. Normally, dopamine transporters carry dopamine back into the cells where it was formed.

-from Page, 1997


120.What area of the brain is affected by high doses of morphine?

A. PituitaryB. CerebrumC. CerebellumD. Medulla oblongata

Jan 01,7Use the following information to answer the next five questions

Use the following additional information to answer the next two questions

Insert diagram on p.4

121.The structure that degenerates and causes blindness in collies is

A. 1B. 2C. 3D. 4

Jan 01,8122.Collies that are bred for long noses and closely set eyes are more likely to have retinal disease. The

best explanation for this is that

A. closely spaced eyes cause retinal degenerationB. breeders intentionally select for these three characteristicsC. genes for these three characteristics are on the same chromosomeD. the abnormal gene that causes retinal disease is on the X chromosome

Jan 01,1Numerical Response7. What is the frequency of the abnormal allele that causes hearing defects in Dalmatians?

Answer: __________

(Record your answer as a value from 0 to 1, rounded to two decimal places in the numerical-response section on the answer sheet.)

Morphine is a drug obtained from the opium plant. It is routinely given to postoperative patients on a short-term basis for pain. At high doses, it causes breathing and heart contraction to become suppressed.

A high percentage of purebred dogs have genetic defects. Some examples of these defects follow.

1 Hip dysplasia, a defect in the hip joints that can cripple a dog, occurs in 60% of golden retrievers.2 Hereditary deafness, due to a recessive autosomal disorder, occurs in 30% of Dalmatians.3 Retinal disease, which may cause blindness, occurs in 705 collies.4 Hemophilia, and X-linked recessive disorder, is common in Labrador retrievers. Dwarfism is also

common in this breed of dog.

-from Lemonick, 1994

Jan 01,9Use the following additional information to answer the next question

123.If the female is bred to one of her male offspring that does not have hemophilia, then the probability of the female offspring of this cross having hemophilia is

A. 0%B. 25%C. 75%D. 100%

Jan 01,10124.The breeding of purebred dogs for certain characteristic related to appearance is blamed for the

disturbing number of genetic defects in these animals. These defects are most likely the result of

A. natural selectionB. non-random matingC. geographic isolationD. high rates of mutation

Jan 02,1Use the following information to answer the first three questions

125.Low levels of calcium ions in the blood cause

A. decreased secretion of PTH and increased deposition of calcium in the bonesB. decreased secretion of calcitonin and increased deposition of calcium in the bonesC. increased secretion of PTH and movement of calcium form the bones to the bloodD. increased secretion of calcitonin and movement of calcium from the bones to the blood

Jan 02,2126.The release of thyroxine from the thyroid is directly regulated by

A. TSHB. TRHC. iodineD. thyroxine

A healthy female Labrador retriever has won several ribbons for her appearance in dog shows. She was mated with two healthy male Labrador retrievers. In the two litters produced, some of the offspring had hemophilia and others were normal.

The thyroid gland secretes the hormone thyroxine and calcitonin. Embedded in the thyroid gland are the four parathyroid glands. The parathyroid glands secrete the parathyroid hormone (PTH). Calcitonin and PTH work antagonistically to maintain homeostasis of calcium ion concentrations in the blood. High levels of calcium ions stimulate the secretion of calcitonin, which causes deposition of calcium in the bones.

Jan 02,3127.A characteristic symptom of hyperthyroidism, a disorder of the thyroid gland, is

A. lethargyB. weight lossC. intolerance to coldD. slowed mental processes

Jan 02,4128.Which of the following hormones plays a role in returning the salt concentration in the blood to

homeostatic levels following heavy exercise?

A. CortisolB. ThyroxineC. AldosteroneD. Epinephrine


129.Diuretic chemicals counteract the effect of the hormone

A. ADHB. insulinC. cortisolD. prolactin

Jan 02,6Use the following information to answer the next five questions

130.Damage to the myelin sheath of an optic neuron affects the speed of neural transmission to the visual centre, which is found in which lobe of the cerebrum?

A. Frontal lobe B. Parietal lobeC. Occipital lobeD. Temporal lobe

Chemicals found in alcohol and tea have a diuretic effect. Diuretics cause the body to produce greater-than-normal volumes of urine.

Multiple sclerosis (MS), a disease of the nervous system, typically has symptoms of uncontrolled muscle responses, weakness, paralysis, and vision difficulties. Researchers believe that MS occurs as a result of the body’s immune system destroying the myelin sheath that surrounds the axon of a nerve cell. The result is a scarring of brain tissue or of spinal cord tissue.

Jan 02,1Numerical Response8. Another symptom of MS is an exaggerated pupillary light reflex. Some of the events that occur during

this reflex are listed below.

1 Motor neuron depolarizes2 Sensory neuron depolarizes3 Interneuron depolarizes4 Light receptors stimulated

The order in which the events listed above occur during a pupillary light reflex is _____, _____, _____, and _____.

(Record all four digits of your answer in the numerical-response section on the answer sheet.)

Jan 02,2Use the following additional information to answer the next three questions

Numerical Response9. What is the resting membrane potential for this neuron, expressed to two digits, and what is the

maximum membrane potential during depolarization, expressed to two digits? (Record your answers as absolute values.)

Answer: _____ _____ , _____ _____Membrane Potential: Resting Maximum

DuringDepolarization

(Record all four digits of your answer in the numerical-response section on the answer sheet.)

Stimulation of a sensory neuron produces an action potential. An abnormal pattern in this action potential can be used to detect MS in its early stages. The graph below illustrates the membrane potential of a normal neuron after stimulation.

Jan 02,7131.Which of the following types of ion movement across an axon membrane would cause the action

potential to change during the interval from 0.2 ms to 0.4 ms?

A. Sodium ions moving into the axonB. Sodium ions moving out of the axonC. Potassium ions moving into the axonD. Potassium ions moving out of the axon

Jan 02,8132.On the graph, the period from 0.5 ms to 1.0 ms represents the neuron’s

A. refractory period, which is when repolarization occursB. refractory period, which is when minimum depolarization occursC. threshold period, which is when repolarization occursD. threshold period, which is when minimum depolarization occurs

Jan 02,9Use the following information to answer the next four questions

133.The site in the neural pathway where MAO is active is the

A. axonB. synaptic cleftC. cell bodyD. Schwann cell

Jan 02,10134.The area of the brain that normally initiates the fight-or-flight response is the

A. ponsB. cerebrumC. cerebellumD. hypothalamus

Monoamine oxidase (MAO) is an enzyme that breaks down the neurotransmitters dopamine, serotonin, and norepinephrine. Individuals who are involved in extreme sports, such as rock climbing, generally have low levels of MAO and, therefore, higher-than-normal levels of these neurotransmitters.

Dopamine and serotonin are linked to pleasurable feelings. Norepinephrine is released in the fight-or-flight response. One hypothesis for why individuals with participate in extreme sports is that in order for individuals with high resting levels of these neurotransmitters to achieve a pleasurable sensation, they require a greater surge of these chemicals than do other people.

-from Zorpette, 1999

Jan 02,11Use the following additional information to answer the next two questions

135.The endorphin met-enkephalin is comprised of the amino acids methionine, phenylalanine, glycine, glycine, and tyrosine. Possible mRNAcodons for the production of met-enkephalin are

A. ATG TTT GGT GGT TATB. ATG TTG GGC GGC TATC. AUG UUC GGT GGT UACD. AUG UUU GGC GGC UAC

Jan 02,12136.When individuals participate in extreme sports, their neurons release more dopamine, which results in

a pleasurable sensation because

A. less serotonin is released from neuronsB. more dopamine receptors are producedC. the fight-or-flight response is inhibitedD. a neuron containing dopamine receptors reaches threshold depolarization

Serotonin stimulates the release of endorphins, and endorphins eventually cause the release of more dopamine. Studies of individuals involved in extreme sports have found that these people have lower-than-normal numbers of two of the five types of dopamine receptors.

-from Zorpette, 1999

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Endocrine and nervous systems and nervous systems… · Web viewendocrine system Jan 96,8 Which sequence correctly shows the path of sound transmission in the ear? Tympanic membrane