Free Sense organs questions for IGCSE Biology (0610), part of Coordination & response. Each question has the answer and the marking points an examiner would look for.
Generate a full Sense Organs worksheet →All Coordination & response questionsA person moves from a dark room into bright light.
What happens in the iris?
| circular muscles | radial muscles | pupil | |
|---|---|---|---|
| A | relax | contract | becomes smaller |
| B | relax | contract | becomes larger |
| C | contract | relax | becomes larger |
| D | contract | relax | becomes smaller |
Answer: D
Which term is described by this statement?
“The change in pupil diameter in response to light intensity.”
Answer: B
The eye changes shape to focus on near and distant objects.
Describe accommodation for a near object.
State the function of the optic nerve.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | ciliary muscles contract, ligaments slack, lens fatter ciliary muscles contract B1 suspensory ligaments slacken B1 the lens becomes fatter/more convex, bending light more B1 | 3 |
| (b) | carries impulses to brain carries impulses from the retina to the brain B1 | 1 |
The eye has several parts.
State the function of the cornea and the iris.
Name the area of the retina with the most cones.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | refracts light; controls pupil size cornea refracts light B1 iris controls the amount of light entering (pupil size) B1 | 2 |
| (b) | fovea fovea B1 | 1 |
The eye responds to light.
Describe the pupil reflex in bright light.
Name the cells in the retina that detect colour.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | circular muscles contract, radial relax, pupil smaller circular muscles of the iris contract B1 radial muscles relax B1 the pupil gets smaller, letting in less light B1 | 3 |
| (b) | cones cones B1 | 1 |
This question is about the eye.
State the functions of the cornea, the retina and the optic nerve.
Describe how the eye focuses on a near object.
Distinguish between the functions of rods and cones.
Explain why it is difficult to see colours in dim light.
Explain why there is a blind spot in each eye.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | cornea refracts light; retina contains light receptors; optic nerve carries impulses to brain cornea refracts (bends) light B1 retina contains light-sensitive receptor cells (rods and cones) B1 optic nerve carries impulses to the brain B1 | 3 |
| (b) | ciliary muscles contract; suspensory ligaments slacken; lens becomes fatter, refracts more ciliary muscles contract B1 suspensory ligaments become slack B1 the lens becomes thicker / more convex and refracts light more B1 | 3 |
| (c) | rods: dim light, black and white; cones: colour, bright light rods detect light in dim light (no colour vision) B1 cones detect colour and work in bright light B1 | 2 |
| (d) | cones need bright light; rods do not detect colour cones need bright light to work B1 rods work in dim light but do not distinguish colours B1 | 2 |
| (e) | no receptor cells where optic nerve leaves there are no light receptors where the optic nerve leaves the retina B1 | 1 |
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Meet Riyaz →Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in