ENT physiology

Question 1

What is the function of the eustachian tube?

Answer 1

Ventilation pathway for middle ear mucosa (allows oxygen into cells)

Question 2

What is the relationship between the oval & round window?

Answer 2

A one goes in the other moves out

Question 3

What is the function of the hair cells in the ear?

Answer 3

Transduction (convesrion of mechanical ‘bending force’ into electrical impulse

Question 4

What generates the AP of cells in the ear?

Answer 4

Stereocilia deflected towards longest causing depolarisation

Question 5

What are the 5 key vestibular ‘end organs’?

Answer 5

Urticle
Sacculae
Lateral, posterior & superior semicircular canals

Question 6

What are the maculae of the utricle & sacculae termed?

Answer 6

Otolith organs

Question 7

What is the function of the otolith organs?

Answer 7

Perception of linear motion (firing stops so you know that the movement has stopped)

Question 8

How do the semicircular cancals relate with each other?

Answer 8

At 90 degree angles

Question 9

What is the vestibuloclear reflex?

Answer 9

A head turns in one direction the liquid pushes against the cochlea and this causes an increase in firing rate and the opposing side has a decrease in firing rate

Question 10

What is seen if there is an issue with the vestibulo-ocular reflex?

Answer 10

Spontaneous nystagmus *flicking of eye back as brain is trying to focus)

Question 11

What is a vestibular schwannoma?

Answer 11

Tumour of VII nerve sheath (schwann) cells

Question 12

What kind of receptors are the receptors for taste & smell?

Answer 12

Chemoreceptors

Question 13

Where are the sensory receptor cells of taste mainly found?

Answer 13

Taste buds

Question 14

What is the life span of a taste receptor cell?

Answer 14

About 10 days

Question 15

What are the 4 types of papillae on the tongie?

Answer 15

Filiform
Fungiform
Vallate
Foliate

Question 16

Which nerve supplies the taste buds of the anterior 2/3rds of the tongue?

Answer 16

Facial nerve

Question 17

Which nerve supplies the taste buds on the posterior 1/3rd of the tongue?

Answer 17

Glossopharyngeal

Question 18

What are the 5 primary tastes?

Answer 18

Salty 
Sour 
Sweet 
Bitter 
Umami

Question 19

What is ageusia?

Answer 19

Loss of taste function

Question 20

What can cause ageusia?

Answer 20

Nerve damage 
Local inflammation (glossitis, radiation, tobacco) 
Some endocrine disorders (diabetes, cushings)

Question 21

What is hyogeusia?

Answer 21

Reduced taste function

Question 22

Causes of hypogeusia?

Answer 22

Chemo & medication

Question 23

What is dysgeusia?

Answer 23

Distortion of taste function

Question 24

Causes of dysgeusia?

Answer 24

Glossitis 
Gum infections 
Tooth decay 
Reflux 
URTI 
Medications 
Neoplasms 
Chemo 
Zinc deficiency

Question 25

Which cells are in the olfactory mucosa?

Answer 25

Olfactory receptor cells
Supporting cells
Basal cells (secrete mucus)

Question 26

What i anosmia?

Answer 26

Inability to smell

Question 27

Cause of anosmia?

Answer 27

Viral infection
Alergy
Nasal polyps
Head injury

Question 28

What is hyposmia?

Answer 28

Reduced ability to smell

Question 29

What may hyposmia be an early sign of?

Answer 29

Parkinson’s disease

Question 30

Causes of dysosmia?

Answer 30

Hallucinations

Interpretation