IGCSE the eye

Identify structure A

• Pupil

• Iris

• Retina

• Lens

Identify structure C

• Motor neurone

• Sensory neurone

• Optic nerve

• Blind spot

State which letter represents the iris

• H

• J

• K

• L

State the letter that represents the retina

• B

• D

• E

• F

Mr Burns reads his book. State the changes that occur in his eye that allow him to do this (tick all that apply)

• Ciliary muscles relax

• Ciliary muscles contract

• Suspensory ligaments tighten

• Suspensory ligaments go slack

• Lens becomes thin

Mr Burns walks from a bright room to a dark room. Describe the changes that occur in his eye that allow him to still see (tick all that apply)

• Pupils dilate (get bigger)

• Radial muscles contract

• Circular muscles contract

• Ciliary muscles contract

• Circular muscles relax

Identify structure H

• Cornea

• Conjunctiva

• Lens

• Aqueous humor

Why must our iris respond to bright light?

• Protect the retina from damage

• Protect the eye

• To stop the eye over-heating

• To allow internal reflection

The position D is known more commonly as the ........

How many muscles control the movement of the eye?

• 1

• 2

• 3

• 4