Chapter 17: Special Senses

Question 1

What is Olfaction

Answer 1

sense of smell

Question 2

what are basal cells

Answer 2

stem cells located at the bases of supporting cells. Live for ~2 months

Question 3

What produces mucus?

Answer 3

olfactory glands (Bowman’s)

Question 4

What is Gustation

Answer 4

sense of taste

Question 5

what are the 5 tastes

Answer 5

1. salty (sodium)
2. sour (hydrogen)
3. sweet (glucose)
4. bitter (caffeine, morphine)
5. umami (amino acids)

Question 6

what are taste buds made up of?

Answer 6

made up of supporting cells, which surround 50 gustatory receptor cells

Question 7

T/F: more than half of the sensory receptors in the body are in the eyes

Answer 7

True

Question 8

4 accessory structures of the eyes

Answer 8

1. Eyelids
2. lacrimal apparatus
3. extrinsic eye muscles
4. eyelashes and eyebrows

Question 9

role of eyelids

Answer 9

shade eyes during sleep, bright light, and foreign objects

Question 10

role of lacrimal apparatus

Answer 10

produces and drains lacrimal fluid (tears).

Question 11

role of extrinsic eye muscles

Answer 11

move each eye. are surrounded by periorbital fat

Question 12

role of eyelashes and eyebrows

Answer 12

help protect eyeballs from foreign objects, sweat, and direct rays of sun

Question 13

components of the fibrous tunic

Answer 13

superficial layer of eyeball;
1. cornea
2. sclera

Question 14

components of the vascular tunic

Answer 14

middle layer of eyeball;
1. choroid (lines inner surface of sclera)
2. iris
3. pupil

Question 15

3 structures in ears

Answer 15

1. external ear:
   - auricle
   - external auditory canal
   - tympanic membrane
2. middle ear
   - auditory tube
   - ossicles
   - oval window
   - round window
3. internal ear
   - bony labrynth
   - membraneous labrynth

Question 16

physiology of hearing

Answer 16

sound waves enter external ear canal and strike the tympanic membrane, pass through ossicles, strike the oval window which increase pressure and vibrates basalar membrane which stimulates hair bundles on the organ of Corti. Hair cells convert mechanical vibrations into receptor potentials which release neurotransmitters that initiate nerve impulses.

Question 17

how is equilibrium maintained

Answer 17

maculae of utricle and saccule detect linear acceleration and deccelerations of head tilts. Cristae in semicircular ducts detect rotational accels/deccels.
Vestibular branhc axons of vesticulocochlear nerves enter brainstem and terminate in medulla and pons.