IGCSE Topic 12 - The Human Eye

What is the name of the tough, white outer layer of the eye?

• Sclera

• Choroid

• Cornea

• Conjunctiva

Which layer inside the eye contains rods and cones?

• Choroid

• Sclera

• Retina

• Optic nerve

Which two parts of the eye help to focus light rays?

• Lens & retina

• Cornea & iris

• Iris & retina

• Lens & cornea

Which layer of tissue prevents light being reflected back out of the eye?

• Cornea

• Choroid

• Sclera

• Blind spot

Which muscle controls the shape of the lens?

• Radial muscle

• Circular muscle

• Ciliary muscle

What happens when the radial muscle contracts?

• The pupil constricts.

• The pupil dilates.

• The lens is stretched thin.

• The lens becomes more round.

Which part of the eye contains the highest concentration of light receptor cells?

• Fovea

• Blind spot

• Optic nerve

• Choroid

What happens when you focus on a distant object?

• The lens becomes more round.

• The radial muscle contracts.

• The suspensory ligaments become loose.

• The ciliary muscle relaxes.

What is the correct route that light rays take as they enter the eye?

• Cornea => conjunctiva => pupil => retina

• Cornea => lens => pupil => retina

• Conjunctiva => cornea => lens => retina

• Conjunctiva => lens => pupil => retina

Where does the optic nerve attach to the eye?

• Fovea

• Ciliary muscle

• Choroid

• Blind spot