Unit 3: The Special Senses

Question 1

More than half of the sensory receptors in the human body are located where?

Answer 1

Eyes

Question 2

A large part of the cerebral cortex is devoted to processing what?

Answer 2

Visual Information

Question 3

What part of the spectrum of electromagnetic radiation can be seen with the eyes?

Answer 3

Visible light (wavelengths between 400 and 700 nm)

Question 4

• Shade the eyes during sleep.
• Protect the eyes from excessive light and foreign objects.
• Spread lubricating secretions over the eyeballs.

Answer 4

Eyelids

Question 5

What do the eyelids consists of from superficial to deep?

Answer 5

Epidermis
Dermis
Subcutaneous Tissue
Fibers of orbicularis oculi muscle
Tarsal plate
Tarsal glands
Conjuctiva

Question 6

Gives support to the eyelids

Answer 6

Tarsal Plate

Question 7

Secrete a fluid to keep the eyelids from adhering to each other.

Answer 7

Tarsal Glands

Question 8

A thin mucous membrane that lines the inner aspect of the eyelids and is reflected onto the anterior surface of the eyebrow.

Answer 8

Conjunctiva

Question 9

Help protect eyeballs from foreign objects, perspirations, and the direct rays of the sun.

Answer 9

Eyelashes and eyebrows

Question 10

Consists of structures that produce and drain tears.

Answer 10

Lacrimal apparatus

Question 11

Move the eyeballs laterally, medially, superiorly, and inferiorly

Answer 11

Six extrinsic eye muscle

Question 12

What does the eyeball contain?

Answer 12

Nonvascular lens

Question 13

This lens fine-tunes the focusing of light rays for clear vision.

Answer 13

Nonvascular lens

Question 14

What is the interior of the eyeball divided into?

Answer 14

Anterior cavity

Vitreous chamber

Question 15

The outer coat of the eyeball

Answer 15

Fibrous Tunic

Question 16

The Fibrous Tunic can be divided into:

Answer 16

The posterior sclera

The anterior cornea

Question 17

An opening at the junction of the sclera and cornea

Answer 17

The scleral venous sinus / canal of Schlemm.

Question 18

• The “white” of the eye.
• A white coat of dense fibrous tissue that covers all the eyeball except the iris.
• Gives shape to the eyeball and protects its inner parts.
• Posterior surface is pierced by the optic nerve.

Answer 18

Sclera

Question 19

• A nonvascular, transparent, fibrous coat through the iris which the iris can be seen.
• Acts in the refraction of light

Answer 19

Cornea

Question 20

The middle layer of the eyeball.

Answer 20

Vascular tunic

Question 21

What are the vascular tunic’s three portions?

Answer 21

The choroid
The ciliary body
The iris

Question 22

• Absorbs light rays so that they are not reflected and scattered within the eyeball.
• Provides nutrients to the posterior surface of the retina.

Answer 22

The choroid

Question 23

Consists of the ciliary processes and ciliary muscle

Answer 23

The ciliary body

Question 24

Part of the ciliary body that consist of protrusions on the internal surface of the ciliary body where epithelial lining cells secrete aqueous humor.

Answer 24

The ciliary processes

Question 25

Part of the ciliary body that is a smooth muscle that alters the shape of the lens for near or far vision.

Answer 25

The ciliary muscle

Question 26

- The colored portion seen through the cornea.

Answer 26

Iris

Question 27

What does the iris consist of that are arranged to form a doughnut-shaped structure?

Answer 27

Circular Iris | Radial Iris

Question 28

- The black hole in the center of the iris. | - The area where light enters the eyeball

Answer 28

Pupil

Question 29

A principal function of the iris

Answer 29

Regulate the amount of light entering the posterior cavity of the eyeball.

Question 30

- The third and inner coat of the eye. - Lines the posterior three-quarters of the eyeball. - Beginning of the visual pathway

Answer 30

Retina (Nervous Tunic)

Question 31

The only place in the body where blood vessels can be viewed and directly examined for pathological changes.

Answer 31

Surface of the Retina

Question 32

The site where the optic nerve hits the eyeball

Answer 32

Optic disc

Question 33

The vessels of the retina that are bundled together with the optic nerve with branches across the retinal surface.

Answer 33

Central retinal artery | vein

Question 34

The retina consists of what?

Answer 34

A pigment epithelium (nonvisual portion) | A neural portion (visual portion)

Question 35

Part of the retina that aids the choroid in absorbing stray light rays.

Answer 35

Pigment epithelium