The eye
Your eye is a sense organ: it turns light into nerve impulses. The coloured iris controls how much light gets in through the black pupil; behind it, a lens focuses the light onto the retina, where millions of receptor cells detect it.
By the end of this page you can
- Explain the pupil reflex, the retina’s receptors and how glasses correct sight
- Relate each part of the eye to its function
- Trace light from the cornea to the brain
- Define accommodation, rods, cones, long and short sight
- Explain how the eye focuses on near and distant objects
Goals tick themselves off as you try the activities below.
Photo: Kamil Saitov, CC BY 4.0, via Wikimedia Commons. Resized, JPEG q68.
The parts you can see from outside: the white sclera, the coloured iris and the black pupil.
How often it shows up in past papers
Paper 1 counts come from our past-paper bank of CSEC Biology Paper 1s. Paper 2 is not included yet.
Control the light, catch it, correct it
The eye controls how much light enters, detects it, and sometimes needs help to focus. Tap each card.
Each part, its job
Tap each part of the eye to see what it does.
What does it do?
Tap a part on the list to see its job.
Glaucoma: fluid pressure builds inside the eye and slowly damages the optic nerve, with no early warning. Eye drops or surgery can control it. It is common among people of African descent, so regular eye tests matter.
The path of light
Put these in the order that light (and then the message) passes through them. Drag or tap each card into its slot.
What is the clear front surface?
Seven terms to know cold
Say what each term means before you flip the card. Accommodation answers need the muscle, the ligaments and the lens.
Six quick questions, then a real one
Pick an answer to see why it’s right or wrong.
Which cells let you see in dim light?
To focus on a near object, the ciliary muscles
A short-sighted person is corrected with
Why can you not see an image that falls on the blind spot?
In bright light the pupil becomes
Glaucoma damages vision because
exam style · 3 marks
Explain how the eye focuses on a book held close to the face.
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Practice questions are written by My V.I.P. Academy. They are not official CXC papers.