$$\mathrm{cGMP} \xrightarrow{\text{phosphodiesterase}} \mathrm{GMP}$$

Question 1

Which of the following best describes the function of mechanoreceptors in the skin?

Accepted Answer

They transduce mechanical forces into changes in membrane potential by opening ion channels.

Question 2

A strong stimulus applied to a stretch receptor in a vertebrate muscle will result in:

Accepted Answer

A higher frequency of action potentials in the axon.

Question 3

Which of the following is TRUE about the receptor potential ($$RP) in $$sensory cells?

Accepted Answer

It is a change in membrane potential in response to a stimulus.

Question 4

In the dark, rod cells in the vertebrate retina are depolarized because:

Accepted Answer

Na$$^+$$ channels are open due to high levels of cGMP.

Question 5

Which molecule directly absorbs light in the human retina, initiating the visual signal?

Accepted Answer

Retinal

Question 6

What is the main difference between ionotropic and metabotropic sensory detection?

Accepted Answer

Ionotropic detection involves direct opening of ion channels by the receptor protein, while metabotropic detection involves a G protein cascade.

Question 7

Which sensory structure is responsible for detecting high-frequency vibrations in the skin?

Accepted Answer

Pacinian corpuscles

Question 8

The star-shaped appendages of the star-nosed mole are best described as:

Accepted Answer

Highly sensitive tactile structures.

Question 9

Which of the following best explains why cephalopod eyes do not have a blind spot?

Accepted Answer

Their photoreceptors are the first thing light hits, so there are no blood vessels or nerves blocking the retina.

Question 10

Which of the following is a real-world example of metabotropic sensory detection?

Accepted Answer

The activation of a G protein cascade in photoreceptor cells when light is absorbed.

Question 11

Which equation best represents the conversion of cGMP to GMP in the phototransduction pathway?

Accepted Answer

$$\mathrm{cGMP} \xrightarrow{	ext{phosphodiesterase}} \mathrm{GMP}$$

Question 12

Which of the following statements about the fovea is correct?

Accepted Answer

It is the area of the retina with the highest density of cone cells, providing the sharpest vision.

Question 13

Which sensory system uses rhodopsins as the primary photoreceptor molecule?

Accepted Answer

Vision

Question 14

Which of the following best describes the function of cone cells in the human retina?

Accepted Answer

They provide color vision and the sharpest visual acuity.

Question 15

Which of the following is NOT a stimulus detected by mechanoreceptors?

Accepted Answer

Odors

Question 16

Which of the following best explains why humans cannot see ultraviolet or infrared light?

Accepted Answer

Human cone cells do not absorb wavelengths below 350 nm or above 750 nm.

Question 17

Which of the following is a plausible explanation for the loss of vision in some moles?

Accepted Answer

Relaxation of selective pressure for vision led to vestigial eyes.

Question 18

Which of the following best describes the compound eye of an arthropod?

Accepted Answer

It consists of many ommatidia, each providing a slightly different view.

Question 19

Which of the following is a real-world example of sensory adaptation?

Accepted Answer

The reduced sensation of clothing on your skin over time.

Sensory Systems: Structure, Function, and Evolution

Study Guide - Practice Questions