Question 1

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

Accepted Answer

The tectorial membrane is part of the spiral organ, which is located in the cochlea of the inner ear. The modiolus is a central bony core of the cochlea, the vestibule is a part of the balance system in the inner ear, the scala tympani is one of the three fluid filled chambers in the cochlea, and the chorda tympani is a nerve that carries taste information from the tongue to the brain.

Question 2

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

1. The sound wave enters the external ear canal and strikes the eardrum (tympanic membrane), causing it to vibrate. 
2. The vibration of the eardrum is transmitted to the ossicles (malleus, incus, and stapes), which amplify and transmit the vibration to the oval window. 
3. The vibration of the oval window causes the perilymph in the cochlea to vibrate. 
4. The vibration of the perilymph causes the endolymph (a fluid in the cochlear duct) to vibrate. 
5. Finally, the vibrations of the endolymph stimulate the hair cells in the Organ of Corti, generating nerve impulses that are transmitted to the brain.

Question 3

The attenuation reflex

Accepted Answer

The attenuation reflex is a protective mechanism that prevents damage to delicate ear structures by reducing the transmission of loud sounds to the inner ear. It does this by contracting the stapedius and tensor tympani muscles, which dampen the vibrations of the ossicles in the middle ear, thus reducing the amount of sound energy that reaches the inner ear. This reflex is important for protecting the delicate hair cells of the cochlea from damage that could lead to hearing loss.

Question 4

Which of the following is true?

Accepted Answer

The bony core of the cochlea is called the modiolus. The cochlear duct is actually filled with endolymph, not perilymph. The foot plate of the stapes (not incus) fits into the oval window. The vestibule is a separate region that contains the utricle and saccule, which are involved in sensing linear acceleration and head position. The spiral organ (or organ of Corti) is found within the cochlea, not the semicircular canals.

Question 5

The superior olivary nucleus

Accepted Answer

The superior olivary nucleus sends efferent impulses that inhibit all hair cells not vibrating maximally through the olivocochlear bundle. This helps to sharpen the tuning curves of the hair cells, allowing for better discrimination of auditory stimuli.

Question 6

The sensory cells for hearing are located in the

Accepted Answer

The organ of Corti, also known as the spiral organ, is the location of the sensory cells for hearing in the inner ear. The other options listed are not associated with hearing sensory cells.

Question 7

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 8

Which of the following sequences is correct?

Accepted Answer

The correct sequence of structures in the inner ear through which sound vibrations travel is: tympanic membrane, malleus, incus, stapes, oval window, vestibule, cochlea, scala vestibuli, cochlear duct, scala tympani, round window. Choice A is the only sequence that follows this order.

Question 9

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 pathway for hearing is from the cochlear nucleus (5), the superior olivary nucleus (3), to the inferior colliculus (1), then to the medial geniculate nucleus (2), and finally to the auditory cortex (4). Choice B represents the correct sequence.

Question 10

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 to the brain for processing. The vestibular portion of the nerve is responsible for transmitting signals related to balance and spatial orientation. The ossicular and tympanic portions are not part of the vestibulocochlear nerve but rather involve the middle ear and eardrum. The spiral portion refers to the shape of the cochlea, not a specific part of the nerve.

Question 11

More sound volume is perceived when

Accepted Answer

The perception of sound volume is directly related to the amplitude (height) of the sound wave. When the amplitude increases, the sound is perceived as louder. Therefore, choice A is the best answer.

Question 12

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

Accepted Answer

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

Question 13

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. When the bundle is deflected by sound waves or other stimuli, the tip links pull on ion channels in the stereocilia, generating an electrical signal that is transmitted to the brain. Calcium channels, spiral ligaments, and outer hair cells are all involved in the function of the inner ear, but they do not directly connect the stereocilia in a hair bundle.

Question 14

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

Accepted Answer

The differences in the time that sound waves take to reach each ear is known as binaural hearing. This is how our brain determines the direction from which a sound is coming. It uses the slight time difference between the sound reaching each ear to locate the sound source.

Question 15

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

Accepted Answer

Timbre is the quality of the sound that distinguishes it from other sounds of the same pitch and loudness. It refers to the unique resonance quality of a sound, which is determined by factors such as the shape and size of the object that produces the sound and the way in which the sound is produced. Therefore, resonance quality is the best definition of timbre.

Question 16

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

Accepted Answer

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

Question 17

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 18

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

Accepted Answer

The chorda tympani is a branch of the facial nerve that carries taste information from the anterior two-thirds of the tongue. If it is damaged in the right ear, it could result in loss of taste on the right anterior two-thirds of the tongue.

Question 19

Cochlear neurons are stimulated by

Accepted Answer

Cochlear neurons are stimulated by bending microvilli or stereocilia on the hair cells. The vibrations of the tectorial membrane and movement of the otoliths in the endolymph are involved in the auditory system, but not specifically in cochlear neurons. Turning the spiral organ is not a recognized mechanism for stimulating cochlear neurons.

Question 20

The round window

Accepted Answer

The round window acts as a mechanical release for waves within the cochlea. As the stapes pushes the oval window in and out, it causes waves to move through the perilymph within the cochlea. The round window, located at the other end of the cochlea, allows for the release of these waves to prevent damage to the cochlear structures.

Quiz 15: The Special Senses

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

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