Question 1

Peripheral shadows or flashes of light can be a sign that the retina is peeling away from the layer below.Why is detachment of the retina a medical emergency?

Accepted Answer

A)  It contains the photoreceptor cells that respond to light.
B)  It is crucial for focusing the image.
C)  It secretes tears that bathe and protect the eyeball.
D)  It is a sphincter muscle that controls light transmission.E) B) and D)
F) C) and D)

Question 2

Mutations in the DFNA20/26 locus, which codes for the actin gamma 1 protein, are associated with congenital deafness.An irate senator complains that government money is being wasted on studies of this mutant gene -- in yeast! "I am no biologist," says the senator, "but I am pretty sure yeast don't have ears." How do you respond?

Accepted Answer

A)  "You are right, Senator -- yeast do not have ears.We should revoke the funding immediately."
B)  "We can learn valuable information about the structure of the mutant protein by expressing it in yeast.It is difficult to collect large amounts of actin from tiny hair cells, and unethical to collect it from human patients."
C)  "We can learn valuable information about the transcription of the mutant gene in yeast.It is much more difficult to study transcription in human cells."
D)  "We can learn valuable information about sound transmission through the mutant yeast.By placing a speaker against a yeast vial and recording sound from the other side, we can infer how the mutant actin affects sound waves."E) A) and B)
F) A) and C)

Question 3

Which taste modality does not involve activation of a G-protein coupled receptor?

Accepted Answer

A)  bitter
B)  sweet
C)  umami
D)  sourE) C) and D)
F) A) and B)

Question 4

What are the short retinal photoreceptors responsible for color vision called?

Accepted Answer

A)  rods
B)  cones
C)  bipolar cells
D)  glial cellsE) B) and C)
F) All of the above

Question 5

Which animal became numerous and widespread by using sonar to enable a high level of activity in the dark?

Accepted Answer

A)  bats
B)  whales
C)  owls
D)  dolphinsE) None of the above
F) All of the above

Question 6

The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli.The gene variant a person has determines how sensitive their neurons are to these compounds.What would you predict for people who have the high-sensitivity variant of hTAS2R38?

Accepted Answer

A)  They will not easily digest turnips and broccoli.
B)  They will have to eat more turnips and broccoli to get the same flavor.
C)  They will dislike turnips and broccoli.
D)  They will become allergic to turnips and broccoli.E) A) and B)
F) All of the above

Question 7

Which is NOT an example of a stimulus sensed by an interoceptor?

Accepted Answer

A)  temperature
B)  vibration
C)  pain
D)  magnetismE) A) and B)
F) A) and C)

Question 8

Which of the following statements about hair cells is NOT true?

Accepted Answer

A)  They are found in the mammalian ear.
B)  They are found in the fish lateral line system.
C)  They can be repaired if they rupture.
D)  Bending of the cells triggers ion flow across the cell membrane.E) B) and D)
F) All of the above

Question 9

The discovery that ATP is a pain-signaling factor immediately suggested what possible therapeutic approach to alleviate chronic pain?

Accepted Answer

A)  create large intracellular aggregates of ATP
B)  treat with an ATP receptor antagonist
C)  block the synthesis of ATP inside cells
D)  use electric stimulation on pain centers of the brainE) None of the above
F) All of the above

Question 10

A research strain of mice has a mutation that causes voltage-gated sodium channels to take longer to return to the active state after a spike.What is the likely consequence for transduction of sensory stimuli?

Accepted Answer

A)  There will be no effect on sensory perception, because sensory information relies on stimulus-gated ion channels and not voltage-gated ion channels.
B)  Sensory information will be incorrectly perceived as high intensity stimuli, due to the increased frequency of action potentials.
C)  The mutation will interfere with the ability of stimuli to create receptor potentials, and thus the neuron will fire with slow, broad action potentials, giving the animal enhanced sensory perception.
D)  Due to a longer refractory period, the neuron will be unable to conduct high frequency action potentials, and thus will not effectively transmit information about strong stimuli.E) A) and D)
F) None of the above

Question 11

Since the optic nerve must pass through the retinal layer, we all have a blind spot devoid of light receptors.This normally goes unnoticed, since the brain attempts to compensate for missing sensory information by filling it in based on surrounding patterns.Which step of the sensory pathway is represented by perceptual filling-in of the physiological blind spot?

Accepted Answer

A)  interpretation
B)  stimulus
C)  transduction into receptor potential
D)  action potential transmissionE) B) and C)
F) All of the above

Question 12

True or false: Humans are unique among animals due to our highly-evolved repertoire of sensory receptors.Although humans have large and highly-developed brains, our sensory receptors are typical of many vertebrates.

Accepted Answer

A) True 
 B)False

Question 13

In the vertebrate eye, what structure controls the amount of light that reaches the retina?

Accepted Answer

A)  fovea
B)  cornea
C)  iris
D)  lensE) All of the above
F) A) and B)

Question 14

The statoliths of a lobster are replaced with iron filings, and a strong magnetic field is produced at the top of its tank.How will the lobster respond?

Accepted Answer

A)  Its dorsal surface will stick to the top of the tank and it will be unable to move.
B)  It will turn upside down and grip the underside of the tank lid.
C)  It will turn upside down and remain at the bottom of the tank.
D)  It will not respond in any way.E) B) and D)
F) All of the above

Question 15

If genetically engineered bees could express a receptor for TNT in their olfactory neurons, what type of receptor would the TNT receptor be?

Accepted Answer

A)  chemoreceptor
B)  mechanoreceptor
C)  electromagnetic receptor
D)  it is a novel type of receptorE) A) and D)
F) A) and C)

Question 16

The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli.Glucosinolates can block synthesis and transport of iodine.Before the advent of iodized salt, this was a particular problem in areas of the world that are naturally low in iodine.Why might the human population include different variants of the hTAS2R38 gene?

Accepted Answer

A)  Areas of high iodine are generally coastal, and turnips and broccoli are not easily grown there.
B)  Iodine created mutations in the hTAS2R38 gene.
C)  Where iodine was low, eating plants rich in glucosinolates helped people metabolize iodine, but where iodine was high they avoided such foods.
D)  Where iodine was low, it was important to avoid foods with glucosinolates, but where iodine was plentiful, palatability of a wider range of plants was beneficial.E) A) and B)
F) All of the above

Question 17

At night, faint objects are best seen when not looked at directly.What is the basis of this phenomenon?

Accepted Answer

A)  Rhodopsin is transported away from the fovea at night.
B)  Cis-retinal builds up in the fovea at night, and is degraded during the day.
C)  Cone photoreceptors are most sensitive in dim light, and few cones are present in the fovea.
D)  Rod photoreceptors are most sensitive in dim light, and few rods are present in the fovea.E) B) and D)
F) None of the above

Question 18

Pit vipers are the only known vertebrates with an ability to detect a certain type of stimulus.What can these snakes sense?

Accepted Answer

A)  infrared radiation
B)  ultraviolet radiation
C)  microwave radiation
D)  visible light radiationE) B) and D)
F) C) and D)

Question 19

Which of type of information is NOT communicated by proprioceptors?

Accepted Answer

A)  muscle temperature
B)  limb movement
C)  muscle position
D)  muscle contractionE) None of the above
F) B) and C)

Question 20

Honeybees can detect a variety of odorants through olfactory receptors on their antennae.You genetically engineer a receptor to be gated by the explosive chemical TNT, and use a transgene to express the receptor in honeybee olfactory neurons.What would this provide to the bee?

Accepted Answer

A)  the ability to taste TNT
B)  it would have no effect
C)  the ability to smell TNT
D)  the ability to collect TNT moleculesE) A) and D)
F) B) and C)

Exam 44: Sensory Systems

Correct Answer
verified

The statoliths of a lobster are replaced with iron filings, and a strong magnetic field is produced at the top of its tank.How will the lobster respond?

Correct Answer
verified

If genetically engineered bees could express a receptor for TNT in their olfactory neurons, what type of receptor would the TNT receptor be?

Correct Answer
verified

What are the short retinal photoreceptors responsible for color vision called?

Correct Answer
verified

Honeybees can detect a variety of odorants through olfactory receptors on their antennae.You genetically engineer a receptor to be gated by the explosive chemical TNT, and use a transgene to express the receptor in honeybee olfactory neurons.What would this provide to the bee?

Correct Answer
verified

True or false: Humans are unique among animals due to our highly-evolved repertoire of sensory receptors.Although humans have large and highly-developed brains, our sensory receptors are typical of many vertebrates.

Correct Answer
verified

Which of type of information is NOT communicated by proprioceptors?

Correct Answer
verified

In the vertebrate eye, what structure controls the amount of light that reaches the retina?

Correct Answer
verified

Correct Answer
verified

A research strain of mice has a mutation that causes voltage-gated sodium channels to take longer to return to the active state after a spike.What is the likely consequence for transduction of sensory stimuli?

Correct Answer
verified

Pit vipers are the only known vertebrates with an ability to detect a certain type of stimulus.What can these snakes sense?

Correct Answer
verified

At night, faint objects are best seen when not looked at directly.What is the basis of this phenomenon?

Correct Answer
verified

Which of the following statements about hair cells is NOT true?

Correct Answer
verified

Correct Answer
verified

Which animal became numerous and widespread by using sonar to enable a high level of activity in the dark?

Correct Answer
verified

The discovery that ATP is a pain-signaling factor immediately suggested what possible therapeutic approach to alleviate chronic pain?

Correct Answer
verified

Which is NOT an example of a stimulus sensed by an interoceptor?

Correct Answer
verified

Which taste modality does not involve activation of a G-protein coupled receptor?

Correct Answer
verified

The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli.The gene variant a person has determines how sensitive their neurons are to these compounds.What would you predict for people who have the high-sensitivity variant of hTAS2R38?

Correct Answer
verified

Peripheral shadows or flashes of light can be a sign that the retina is peeling away from the layer below.Why is detachment of the retina a medical emergency?

Correct Answer
verified

Exam 44: Sensory Systems

Correct AnswerverifiedShow Answer

The statoliths of a lobster are replaced with iron filings, and a strong magnetic field is produced at the top of its tank.How will the lobster respond?

Correct AnswerverifiedShow Answer

If genetically engineered bees could express a receptor for TNT in their olfactory neurons, what type of receptor would the TNT receptor be?

Correct AnswerverifiedShow Answer

What are the short retinal photoreceptors responsible for color vision called?

Correct AnswerverifiedShow Answer

Honeybees can detect a variety of odorants through olfactory receptors on their antennae.You genetically engineer a receptor to be gated by the explosive chemical TNT, and use a transgene to express the receptor in honeybee olfactory neurons.What would this provide to the bee?

Correct AnswerverifiedShow Answer

True or false: Humans are unique among animals due to our highly-evolved repertoire of sensory receptors.Although humans have large and highly-developed brains, our sensory receptors are typical of many vertebrates.

Correct AnswerverifiedShow Answer

Which of type of information is NOT communicated by proprioceptors?

Correct AnswerverifiedShow Answer

In the vertebrate eye, what structure controls the amount of light that reaches the retina?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A research strain of mice has a mutation that causes voltage-gated sodium channels to take longer to return to the active state after a spike.What is the likely consequence for transduction of sensory stimuli?

Correct AnswerverifiedShow Answer

Pit vipers are the only known vertebrates with an ability to detect a certain type of stimulus.What can these snakes sense?

Correct AnswerverifiedShow Answer

At night, faint objects are best seen when not looked at directly.What is the basis of this phenomenon?

Correct AnswerverifiedShow Answer

Which of the following statements about hair cells is NOT true?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which animal became numerous and widespread by using sonar to enable a high level of activity in the dark?

Correct AnswerverifiedShow Answer

The discovery that ATP is a pain-signaling factor immediately suggested what possible therapeutic approach to alleviate chronic pain?

Correct AnswerverifiedShow Answer

Which is NOT an example of a stimulus sensed by an interoceptor?

Correct AnswerverifiedShow Answer

Which taste modality does not involve activation of a G-protein coupled receptor?

Correct AnswerverifiedShow Answer

The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli.The gene variant a person has determines how sensitive their neurons are to these compounds.What would you predict for people who have the high-sensitivity variant of hTAS2R38?

Correct AnswerverifiedShow Answer

Peripheral shadows or flashes of light can be a sign that the retina is peeling away from the layer below.Why is detachment of the retina a medical emergency?

Correct AnswerverifiedShow Answer

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verified

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Correct Answer
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