Q: Which of the following equations correctly represents the conversion of ATP to cAMP during olfactory transduction?

$$\mathrm{ATP} \xrightarrow{\text{adenylyl cyclase}} \mathrm{cAMP} + \mathrm{PP_i}$$

Question 1

Which of the following best describes the process by which an odorant molecule leads to the generation of an action potential in an olfactory receptor cell?

Accepted Answer

Odorant binds to receptor, activating a G protein, which increases cAMP, opening Na+ channels and causing depolarization.

Question 2

A patient presents with a loss of taste sensation on the anterior two-thirds of the tongue. Which cranial nerve is most likely affected?

Accepted Answer

Facial nerve (VII)

Question 3

Which type of lingual papillae contains the highest number of taste buds and is arranged in a 'V' shape near the posterior margin of the tongue?

Accepted Answer

Vallate (circumvallate) papillae

Question 4

Which of the following best explains why a person with a vitamin A deficiency may experience night blindness?

Accepted Answer

Vitamin A is required for the synthesis of retinal, a component of rhodopsin in rods.

Question 5

Which structure in the ear is responsible for detecting rotational movements of the head?

Accepted Answer

Semicircular ducts

Question 6

A patient has difficulty hearing high-frequency sounds. Which part of the cochlea is most likely damaged?

Accepted Answer

Basilar membrane near the oval window

Question 7

Which of the following statements about the lens of the eye is correct?

Accepted Answer

A rounder lens increases refraction and is used for focusing on near objects.

Question 8

Which of the following best describes the function of the otolithic membrane in the vestibule?

Accepted Answer

It moves in response to gravity and linear acceleration, bending hair cells to signal head position.

Question 9

Which of the following equations correctly represents the conversion of ATP to cAMP during olfactory transduction?

Accepted Answer

$$\mathrm{ATP} \xrightarrow{	ext{adenylyl cyclase}} \mathrm{cAMP} + \mathrm{PP_i}$$

Question 10

A person is unable to equalize pressure between the middle ear and the nasopharynx during a flight. Which structure is most likely blocked?

Accepted Answer

Pharyngotympanic (auditory) tube

Question 11

Which of the following best explains why the cornea is highly sensitive to touch?

Accepted Answer

It contains numerous free nerve endings.

Question 12

Which of the following is the correct order of structures that sound waves pass through from the external environment to the cochlea?

Accepted Answer

Tympanic membrane → Malleus → Incus → Stapes → Oval window

Question 13

Which of the following best describes the 'dark current' in rods?

Accepted Answer

It is the influx of Na+ ions kept open by cGMP, causing rods to remain depolarized in the dark.

Question 14

Which of the following is a correct statement about the neural pathway for taste sensation?

Accepted Answer

Taste receptor cells synapse with sensory neurons that travel via cranial nerves VII, IX, and X to the medulla oblongata.

Question 15

Which of the following best explains why a person with nonfunctional cones would have difficulty seeing in bright light?

Accepted Answer

Cones are responsible for color vision and high acuity in bright light.

Question 16

Which of the following best describes the effect of contraction of the sphincter pupillae muscle?

Accepted Answer

It decreases the diameter of the pupil (constriction).

Question 17

Which of the following is the correct sequence for the visual pathway from the retina to the brain?

Accepted Answer

Photoreceptors → Bipolar cells → Ganglion cells → Optic nerve → Thalamus → Occipital cortex

Chapter 17: The Special Senses – Olfaction, Gustation, Hearing, Equilibrium, and Vision

Study Guide - Practice Questions

Study Guide - Flashcards