Question 1

Cochlear neurons are stimulated by

Accepted Answer

Cochlear neurons are stimulated by bending microvilli or stereocilia on the hair cells.

Question 2

Which of the following definitions best describes the timbre of sounds?

Accepted Answer

Timbre refers to the unique quality or color of sound that allows us to distinguish one instrument or voice from another, even when they are playing the same note at the same volume. This quality is affected by factors such as the instrument's shape, size, material, and how it is played or sung, which all contribute to the resonance quality of the sound. Therefore, the best definition of timbre is resonance quality (choice D). The other options are related to different aspects of sound but do not fully capture the complexity and uniqueness of each sound's timbre.

Question 3

Arrange the following structures in the order in which they would vibrate as a result of the tympanic membrane vibrating. (1) oval window
(2) vestibular membrane and endolymph
(3) ossicles
(4) basilar membrane
(5) perilymph

Accepted Answer

The tympanic membrane vibrates the malleus, incus, and stapes (the ossicles) first (3), which then vibrates the oval window (1) and introduces vibrations into the perilymph (5). These vibrations then move through the cochlea and cause the vestibular membrane and endolymph (2) to vibrate, which in turn causes the basilar membrane (4) to vibrate. Therefore, the correct order is 3, 1, 5, 2, 4. Choice D matches this order.

Question 4

Which of the following is true?

Accepted Answer

The bony core of the cochlea is indeed called the modiolus.

A) The cochlear duct is actually filled with endolymph, not perilymph. 
C) The foot plate of the stapes fits into the oval window, not the round window. 
D) The vestibule is a separate structure within the inner ear, located adjacent to the cochlea. It contains the utricle and saccule, which contribute to balance and spatial awareness. The organ of Corti is located within the cochlea itself. 
E) The spiral organ (or organ of Corti) is indeed found within the cochlea, but not in the semicircular canals, which are involved in detecting rotational movements of the head.

Question 5

The round window

Accepted Answer

The round window acts as a mechanical release for waves within the cochlea, which helps to maintain the appropriate pressure within the cochlea during sound transmission. This allows for proper movement of the basilar membrane, which ultimately leads to auditory signal transduction. The other answer choices are not accurate descriptions of the function of the round window.

Question 6

The attenuation reflex

Accepted Answer

The attenuation reflex, also known as the acoustic reflex, is a protective mechanism that reduces the transmission of sound to the inner ear in response to loud sounds. This helps to prevent damage to the delicate structures within the ear, such as the hair cells in the cochlea. Therefore, choice C is the correct answer. Choices A and B are incorrect because the attenuation reflex reduces the intensity of sounds, rather than amplifying or enhancing them. Choice D is incorrect because the scala vestibuli and the scala tympani are both parts of the cochlea, but they are not directly involved in the attenuation reflex. Choice E is incorrect because the attenuation reflex does not vibrate the tympanic membrane, but rather affects the activity of the middle ear muscles that control the movement of the ossicles.

Question 7

The direction from which a sound is coming can be determined by the

Accepted Answer

Differences in the time that sound waves take to reach each ear (also known as interaural time differences) are used by the brain to determine the direction from which a sound is coming. This is because the sound wave reaches the ear closest to the sound source slightly before it reaches the other ear, allowing the brain to localize the sound. The other choices may provide information about the sound itself, but not the direction from which it is coming.

Question 8

Arrange the following structures in the order in which they vibrate when a sound wave enters the ear. (1) eardrum
(2) endolymph
(3) ossicles
(4) oval window
(5) perilymph

Accepted Answer

When a sound wave enters the ear, it first reaches the eardrum (1), causing it to vibrate. The vibrations are then transmitted to the ossicles (3), which include the malleus, incus, and stapes. As the stapes vibrates, it pushes on the perilymph (5) in the scala vestibuli of the cochlea, causing it to move. This movement then causes the oval window (4) to vibrate, which then puts pressure on the endolymph (2) in the scala media, leading to the stimulation of the hair cells in the organ of Corti. Therefore, the correct order of structures in terms of their vibration due to a sound wave entering the ear is 1, 3, 4, 5, 2, leading to choice E as the correct answer.

Question 9

The superior olivary nucleus

Accepted Answer

The superior olivary nucleus sends efferent impulses that inhibit all hair cells not vibrating maximally, through the medial olivocochlear bundle. This efferent system is thought to play a role in enhancing the detection of signals in noise and protecting the inner ear from damage due to overstimulation.

Question 10

What connects the stereocilia in a hair bundle?

Accepted Answer

Tip links are protein filaments that connect the tips of the stereocilia in a hair bundle. These links allow for the opening of ion channels and activation of the hair cell in response to mechanical stimuli. Calcium channels, spiral ligaments, and outer hair cells are not directly involved in the connection of the stereocilia in a hair bundle.

Question 11

Arrange the following list of membranes in correct sequence. (1) tectorial membrane
(2) vestibular membrane
(3) tympanic membrane
(4) basilar membrane

Accepted Answer

The answer of Arrange the following list of membranes in...

Question 12

More sound volume is perceived when

Accepted Answer

The amplitude of a sound wave determines its intensity, which is perceived as the loudness or volume of the sound. As the amplitude increases, more energy is transferred to the ear and the brain perceives a louder sound.

Question 13

Which of the following is part of the spiral organ (organ of Corti)?

Accepted Answer

The tectorial membrane is a part of the spiral organ or organ of Corti, which is responsible for converting sound waves into neural signals. The modiolus is a bony central core of the cochlea that contains the spiral ganglion, which connects the inner ear to the brain. The vestibule is a portion of the inner ear that contains the utricle and saccule, which are responsible for sensing position and movement of the head. The scala tympani is a fluid-filled channel that runs through the cochlea, while the chorda tympani is a nerve that carries taste sensation from the tongue to the brain.

Question 14

As a stereocilium bends, the tip link pulls ______ gates open.

Accepted Answer

The answer of As a stereocilium bends, the tip link...

Question 15

Arrange the following parts of the neuronal pathway for hearing in the correct sequence. (1) inferior colliculus
(2) medial geniculate nucleus
(3) superior olivary nucleus
(4) auditory cortex
(5) cochlear nucleus

Accepted Answer

The correct sequence of the neuronal pathway for hearing is cochlear nucleus (5), superior olivary nucleus (3), inferior colliculus (1), medial geniculate nucleus (2), and auditory cortex (4). Choice B follows this sequence correctly.

Question 16

Auditory impulses are transmitted by the _____ portion of the vestibulocochlear nerve.

Accepted Answer

The cochlear portion of the vestibulocochlear nerve is responsible for transmitting auditory impulses from the cochlea of the inner ear to the brain. The vestibular portion of the nerve is responsible for transmitting information about balance and spatial orientation. The spiral portion is not a recognized term in relation to the vestibulocochlear nerve. The ossicular and tympanic portions are not parts of the vestibulocochlear nerve, but rather are related to the middle ear.

Question 17

The sensory cells for hearing are located in the

Accepted Answer

The organ of Corti or spiral organ located within the cochlea of the inner ear contains sensory cells called hair cells, which are responsible for hearing.

Question 18

Which of the following sequences is correct?

Accepted Answer

The answer of Which of the following sequences is correct?
...

Question 19

Damage to the chorda tympani in the right ear could result in loss of taste on the right anterior two-thirds of the tongue.
TRUE

Accepted Answer

The chorda tympani is a branch of the facial nerve that carries taste sensations from the anterior two-thirds of the tongue. Damage to it can impair taste on the affected side.

Question 20

Which of the following is a part of the bony labyrinth?

Accepted Answer

The answer of Which of the following is a part...

Quiz 15: The Special Senses