Exercise 23: Special Senses: Anatomy of the Visual System

Question 1

The eyeball is wrapped in adipose tissue within the bony orbit. What is the function of the adipose tissue?

Answer 1

Adipose tissue protects the eyeball from the outer environments and works as cushion for eyeball

Question 2

Why does one often have to blow one’s nose after crying?

Answer 2

Some percent of your tears is released into the nasolacrimal duct, then sent to the nasal cavity

Question 3

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye laterally

Answer 3

Lateral rectus

Question 4

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye medially

Answer 4

Medial rectus

Question 5

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye up and laterally

Answer 5

Inferior oblique

Question 6

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye down and medially

Answer 6

Inferior rectus

Question 7

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye up and medially

Answer 7

Superior rectus

Question 8

What is the extrinsic eye muscle predominantly responsible for this action: turns the eye down and laterally

Answer 8

Superior oblique

Question 9

What is a sty?

Answer 9

An inflammation of one of the ciliary glands or a small oil gland is a sty

Question 10

What is conjunctivitis?

Answer 10

An inflammation of the conjunctiva

Question 11

Fluid filling the anterior segment of the eye

Answer 11

Aqueous humor

Question 12

The “white” of the eye

Answer 12

Sclera

Question 13

Part of the retina that lacks photoreceptors

Answer 13

Optic disc

Question 14

Modification of the choroid that contains the ciliary muscle

Answer 14

Ciliary body

Question 15

Drains aqueous humor from the eye

Answer 15

Scleral venous sinus

Question 16

Layer containing the rods and cones

Answer 16

Retina

Question 17

Substance occupying the posterior segment of the eyeball

Answer 17

Vitreous humor

Question 18

Forms the bulk of the heavily pigmented vascular layer

Answer 18

Choroid

Question 19

Composed of smooth muscle structures (2)

Answer 19

Ciliary body and iris

Question 20

Area of critical focusing and detailed color vision

Answer 20

Fovea centralis

Question 21

Form the aqueous humor

Answer 21

Ciliary processes of the ciliary body

Question 22

Light-bending media of the eye (4)

Answer 22

Aqueous humor, cornea, lens, vitreous humor

Question 23

Anterior continuation of the sclera - your “window on the world”

Answer 23

Cornea

Question 24

Composed of tough, white, opaque, fibrous connective tissue

Answer 24

Sclera

Question 25

The axons of the _____ cells form the optic nerve, which exits from the eyeball.

Answer 25

Ganglion

Question 26

The dim light receptors are the _____. Only _____ are found in the fovea centralism, whereas mostly _____ are found in the periphery of the retina. _____ are the photoreceptors that operate best in bright light and allow for color vision.

Answer 26

Rods; cones; rods; cones

Question 27

What does the retina look like?

Answer 27

Delicate white membrane overlying the darkly pigmented choroid coat

Question 28

At what point is the retina attached to the posterior aspect of the eyeball?

Answer 28

Optic disc

Question 29

The visual pathway to the occipital lobe of the brain consists most simply of a chain of five cells. Beginning with the photoreceptor cell of the retina, name them, and note their location in the pathway.

Answer 29

1. Photoreceptor cell; retina
2. Bipolar cell; retina
3. Ganglion cell; retina
4. Neuron; lateral geniculate nucleus of the thalamus
5. Cortical neuron; visual cortex of the cerebral hemisphere

Question 30

How is the right optic tract anatomically different from the right optic nerve?

Answer 30

The right optic nerve contains fibers from the right eye only; the right optic tract contain fibers from the lateral aspect of the right eye