Unit 20: Special Senses

Question 1

What is the conjunctiva?

Answer 1

Covers the anterior sclera, vascular mucous membrane. When the vessels dilate, it results in bloodshot eyes

Question 2

The sclera, cornea, and conjunctiva combine to make up what?

Answer 2

Fibrous tunic

Question 3

What purpose does the ciliary body (anterior) of the eye serve?

Answer 3

The ciliary muscle and ciliary processes focus the lens of the eye

Question 4

The choroid (posterior), ciliary body (anterior), iris, and pupil make up what?

Answer 4

Vascular tunic

Question 5

What is the common name for the nervous (sensory) tunic of the eye?

Answer 5

Retina

Question 6

What are the 4 components of the nervous tunic?

Answer 6

Outer pigmented layer
Inner neural layer
Fovea centralis
Optic disk

Question 7

This area of the eye is where light is focused and is the area of greatest visual acuity. There are only cones, and no rods

Answer 7

Fovea centralis

Question 8

What 3 layers make up the inner neural layer of the eye?

Answer 8

Photoreceptors (rods & cones)

Bipolar cells

Ganglion cells

Question 9

What is another name for the optic nerve?

Answer 9

Cranial Nerve II

Question 10

This area of the eye contains aqueous humor (fluid similar to plasma)

Answer 10

Anterior segment

Question 11

This area of the eye contains vitreous humor (gel-like)

Answer 11

Posterior segment

Question 12

What are the parts of the external ear?

Answer 12

Auricle (pinna)

External auditory canal (meatus)

Tympanic membrane (eardrum)

Question 13

Name the ear ossicles

Answer 13

Malleus

Incus

Stapes

Question 14

What makes up the middle ear?

Answer 14

Eustachian tube & ear ossicles

Question 15

This part of the inner ear contains perilymph

Answer 15

Bony labyrinth

Question 16

What are the parts of the bony labyrinth?

Answer 16

Semicircular canals (equilibrium)

Vestibule (equilibrium)

Cochlea (hearing)

Question 17

The membranous labyrinth contains endolymph and is surrounded by bony labyrinth. What does it include?

Answer 17

Semicircular duct (inside canals)

Utricle and saccule (inside vestibule)

Cochlear duct (inside cochlea)

Question 18

Each coil of the cochlea has 3 channels:

Answer 18

Scala vestibuli (upper, perilymph)

Scala tympani (lower, perilymph)

Cochlear duct (middle, endolymph)

Question 19

What membranes are in the cochlea?

Answer 19

-Vestibular membrane (between cochlear duct and scala vestibuli)
-Basilar membrane (between cochlear duct and scala tympani)
-Tectorial membrane (covers hair/receptor cells)

Question 20

What are the receptors in the inner ear?

Answer 20

Called hair cells, which synapse with neurons and send impulses to the brain via cranial nerve VIII