The Eye and Muscle (4.3.6)

Question 1

What is the conjunctiva?

Answer 1

-Thin transparent membrane covering the cornea
-Protects the cornea from damage

Question 2

What is the sclera?

Answer 2

-Tough opaque connective tissue covering the eye- replaced by transparent cornea at the front
-Protects against damage; site of attachment of eye muscles

Question 3

What is the cornea?

Answer 3

-Front transparent part of the sclera
-Transparent and most refraction (bending) of light occurs here

Question 4

What is the aqueous humour?

Answer 4

-Transparent watery fluid between cornea and lens
-Maintains the shape of the front part of the eye

Question 5

What is the iris?

Answer 5

-Muscular layer with both circular and radial muscle; contains pigment that absorbs light
-Adjusts the size of the pupil to control the amount of light entering the eye

Question 6

What is the pupil?

Answer 6

-Gap within the iris
-The area through which light reaches the lens and enters the centre of the eye

Question 7

What is the ciliary body?

Answer 7

-Contains a muscular ring of ciliary muscle around the eye; suspensory ligaments extend from the ciliary body and hold the lens in place
-Adjusts the shape of the lens to focus light rays

Question 8

What are suspensory ligaments?

Answer 8

-Ligaments that connect the ciliary body to the lens
-Transfers tension in the wall of the eyeball to make the lens thinner; important when focusing on distant objects