DHUBS 2 - WEEK 12 - EXAM

Question 1

What are the names of the ossicles of the inner ear?

Answer 1

Malleus
Incus
Stapes

Question 2

What are the names of the muscles of the middle ear?
What is their purpose/function?

Answer 2

Tensor tympani and stapedius muscles dampen ossicle movement and reduce amplitude.

Question 3

What movements are detected by each of the semicircular canals?

Answer 3

Anterior – detects forward rotations of the head.

Posterior – detects backward movements of the head.

Horizontal – detects side to side rotations.

Question 4

What movements are detected by the Utricle and Saccule?

Answer 4

Utricle:
Approximately horizontally orientated.
Detects anterior-posterior and lateral linear movements.

Saccule:
Approximately vertically orientated.
Detects anterior-posterior and vertical linear movements.

Question 5

What is the process of sound travelling through the ear?

Answer 5

Outer ear: The pinna collects soundwaves and directs them down the ear canal to the eardrum.

Middle ear: The eardrum vibrates, transmitting these vibrations through the ossicles - the malleus, incus and stapes.

Inner ear: The vibrations create waves in the cochlear fluid, stimulating hair cells in the cochlea. These cells convert vibrations into electrical signals, which is received by the brain.

Question 6

What are the cranial nerves contributing to taste?

Answer 6

Facial nerve (CNVII)
Glossopharyngeal nerve (CNIX)
Vagus nerve (CNX)

Question 7

What are the 5 basic types of taste?
* How is each one detected by the tongue?

Answer 7

Sweet sensitive taste buds detect the presence of glucose or other sweet substances like fructose or aspartame.

Salt taste buds detect the presence of sodium ions.

Sour taste buds detect the presence of hydrogen ions, i.e. acidity.

Bitter detect a number of different bitter tasting molecules.

Savory taste buds detect L-glutamate, often found in meat.

Question 8

What are the three types of hearing loss?
* Name examples that cause each type of hearing loss.

Answer 8

Conductive Hearing Loss:
Occurs when sound waves are blocked from reaching the inner ear.
Causes may include earwax buildup, fluid in the middle ear, or damage to the eardrum or ossicles.

Sensorineural Hearing Loss:
Results from damage to the inner ear (cochlea) or the auditory nerve.
Causes may include aging, noise exposure, genetic factors, or certain diseases.

Mixed Hearing Loss:
A combination of both conductive and sensorineural hearing loss.