OCR GCSE Biology A: The eye, eye defects, the brain and limits of treatment (J247) – Practice Questions

These are original questions written for Marlbridge, for revision and practice on this content. They are not reproduced past-paper questions, and they do not replicate the exam’s exact structure, question count or mark tariffs – examination boards hold copyright in their own papers. Use these alongside the official past papers from your board or school.

These questions follow the OCR GCSE (9-1) Gateway Science Biology A (J247) specification, Version 4.0 (August 2026), for first assessment in 2018, statements B3.1d to B3.1h. Questions marked (Higher Tier only) test B3.1g or B3.1h, which are in bold in the specification. All others suit both tiers. Revise with the study guide and the revision notes. See also the hub, checklist and diagnostics.

Questions

1. State the function of each of these parts of the eye: (a) the cornea, (b) the iris, (c) the optic nerve. [3]

2. A person looks up from a book at a mountain in the distance. Explain how the eye changes so that the image of the mountain is focused on the retina. [4]

3. A scientist measures the diameter of a volunteer’s pupil in three light conditions.

Light level	Dim	Medium	Bright
Pupil diameter (mm)	6.4	4.0	2.0

(a) Calculate the percentage decrease in diameter from dim to bright light. [2] (b) The area of a circle is π × (diameter ÷ 2)². Calculate how many times larger the area of the pupil is in dim light than in bright light. [3] (c) Explain how the iris changes the size of the pupil in bright light. [2]

4. Short-sightedness is linked to the length of the eyeball. A clinic measures the eyeball length of five people with normal vision and five short-sighted people.

Group	Eyeball length (mm)
Normal vision	24.0, 24.1, 23.9, 24.0, 24.2
Short-sighted	26.1, 25.8, 26.4, 26.0, 25.7

(a) The mean for the normal group is 24.04 mm. Calculate the mean for the short-sighted group and the percentage by which it is longer than the normal mean. Give the percentage to 1 decimal place. [3] (b) Explain why a longer eyeball makes distant objects look blurred. [2] (c) Name the type of lens used in glasses to correct short-sightedness and state what it does to the light. [2]

5. Describe long-sightedness. Include the symptom, a cause, where the light is focused and how glasses correct it. [4]

6. Colour blindness affects the way some people see red and green. (a) Name the cells in the retina that are affected. [1] (b) Explain why glasses with a lens cannot cure colour blindness in the way they can correct short-sightedness. [2]

7. Match each description to the part of the brain affected: cerebrum, cerebellum, medulla, hypothalamus or pituitary. (a) A person understands words but loses the ability to speak. [1] (b) A person’s body temperature is no longer controlled when the weather changes. [1] (c) A person falls over easily because their movements are poorly coordinated. [1] (d) A person’s breathing rate does not increase after exercise. [1] (e) A gland releases hormones that act on other glands. [1]

8. (Higher Tier only) Researchers studied 45 patients, all with damage to the same small region of the cerebrum. 18 of the patients had difficulty with speech. The other 27 did not. (a) Calculate the percentage of patients with difficulty with speech. [1] (b) A student concludes that this region is the only area controlling speech. Evaluate this conclusion using the data and your own knowledge. [3] (c) Suggest one ethical issue the researchers must consider. [2]

9. (Higher Tier only) A team wants to find out which part of the cerebrum is used in remembering faces. They plan to recruit people who have injuries to the front of the brain. Explain two difficulties they will have in obtaining or interpreting their case studies. [4]

10. (Higher Tier only) Explain three reasons why it is difficult to treat damage to the brain or spinal cord. [6]

11. Describe the path taken by light from a book to the point where the person becomes aware of the image. Include the parts of the eye and the part of the brain involved. [6]

12. (Higher Tier only) A patient has a tumour in the hypothalamus. (a) State two functions of the hypothalamus that may be affected. [2] (b) Explain why it is difficult to remove a tumour from deep in the brain without harming the patient. [4]

Answers

1. (a) The cornea refracts (bends) light and lets it in to the eye. [1] (b) The iris controls the size of the pupil, so it controls how much light enters. [1] (c) The optic nerve sends impulses from the retina to the brain. [1] [3] Examiner insight: Answers usually earn credit when each function is stated precisely. Saying the iris “lets light in” is a common slip, because the opening is the pupil.

2. The ciliary muscle relaxes. [1] The suspensory ligaments become taut (pulled tight). [1] The lens is pulled thinner and flatter. [1] Light is refracted less, so the parallel rays from the distant mountain focus on the retina. [1] [4] Examiner insight: Four linked changes are asked for, so give them in order. Saying the ligaments “relax” or the lens “contracts” tends to lose credit, because only the ciliary muscle is muscle.

3. (a) (6.4 − 2.0) ÷ 6.4 × 100 [1] = 68.8% (decrease) [1] (b) Area in dim light = π × 3.2² = 32.2 mm² [1]; area in bright light = π × 1.0² = 3.14 mm² [1]; 32.2 ÷ 3.14 = 10.2 times larger [1] (c) The circular muscles in the iris contract [1] and the radial muscles relax, making the pupil smaller [1] [7] Examiner insight: Show the substitution into the formula, and include the unit and the word “decrease” with a percentage change.

4. (a) Mean = (26.1 + 25.8 + 26.4 + 26.0 + 25.7) ÷ 5 = 26.0 mm [1]; difference = 26.0 − 24.04 = 1.96 mm [1]; 1.96 ÷ 24.04 × 100 = 8.2% [1] (b) The focus for a distant object forms before the retina [1], so the retinal image is out of focus (blurred) [1] (c) A concave (diverging) lens [1]; it spreads the light a little before it enters the eye so the focus moves back onto the retina [1] [7] Examiner insight: For a percentage difference, divide by the reference value (the normal mean), not by the new value.

5. Near objects are blurred, but distant objects are clearer [1]. The eyeball is too short (or the lens is too weak and cannot become curved enough) [1]. Light from near objects would focus behind the retina [1]. A convex (converging) lens is worn, which refracts the light more so the focus moves onto the retina [1] [4] Examiner insight: Link each cause (“too long”, “too short”) to the right defect.

6. (a) Cone cells [1] (b) The problem is in the cone cells, which are faulty or missing, not in where the light is focused [1]; a lens only changes the focus and cannot make the cones work [1] [3] Examiner insight: Saying “rod cells” for colour vision, or that a filter “cures” the condition, does not match the biology.

7. (a) Cerebrum [1] (b) Hypothalamus [1] (c) Cerebellum [1] (d) Medulla [1] (e) Pituitary [1] [5] Examiner insight: Match the symptom to the function, not to the first part that comes to mind.

8. (a) 18 ÷ 45 × 100 = 40% [1] (b) 27 of the 45 patients (60%) did not have difficulty with speech, so the region is not the only area, or not essential for speech in every patient [1]; other regions may share or take over the job [1]; with only 45 patients and no information on the patients before the injury, the sample and evidence are limited [1] (c) Patients may not be able to give informed consent after brain damage [1], so they cannot agree freely to take part [1] (or confidentiality of medical information, with a reason; one issue only, explained) [6] Examiner insight: An evaluate answer should use figures from the data and give a judgement. The ethical point needs a reason; “it is wrong” alone is a statement, not an explanation.

9. Difficulty 1: such injuries are rare, so few people are available [1], and each injury is in a slightly different place and of a different size, so the results are hard to compare [1]. Difficulty 2: the team will not know how well the person recognised faces before the injury [1], and other brain regions may be damaged as well or may compensate, so the face-recognition problem cannot be tied to one area [1] [4] Examiner insight: Each difficulty needs a statement and a consequence. Two points that are really the same idea, such as “too few people” and “small sample”, read as one.

10. Neurones in the brain and spinal cord are not readily replaced, so lost function may not return [1]; treatments tend to relieve symptoms rather than repair tissue [1]. Surgery or radiation can damage healthy tissue around the target [1]; such damage is irreversible and can cause new problems [1]. The brain is inside the skull and the spinal cord in the backbone, so deep parts are hard to reach [1]; operating there risks further harm to delicate tissue [1] [6] Examiner insight: Three separate reasons are asked for, each with an explanation. Use the second point of each reason for the consequence, not a repeat.

11. Light passes through the cornea, which refracts it [1]. It passes through the pupil, whose size is controlled by the iris [1]. The lens refracts the light further and changes shape to focus it [1]. An image is formed on the retina [1], where rods and cones detect the light and produce impulses [1]. The optic nerve carries the impulses to the brain, where the cerebrum processes them so the person is aware of the image [1] [6] Examiner insight: A sequence question rewards the correct order and the right terms. Putting the retina before the lens, or saying that light travels along the optic nerve, undermines an otherwise full answer.

12. (a) Monitors and controls body temperature [1]; monitors and controls water balance (or controls the pituitary gland) [1] (b) It is deep inside the brain, so the surgeon has to reach it through the skull and other tissue [1]; healthy nervous tissue next to the tumour may be damaged during removal [1]; neurones do not readily regrow, so the damage may be permanent [1]; the hypothalamus controls important functions and the pituitary, so even small damage may have large effects [1] [6] Examiner insight: Link the position of the tumour to a specific consequence, and avoid saying the brain “cannot heal at all”, because repair is limited rather than absent.

Where marks are usually lost

• Saying the iris “lets light in” instead of controlling pupil size.
• Writing that ligaments contract. The ciliary muscle contracts or relaxes.
• Reversing the lens: concave for short-sight, convex for long-sight.
• Giving “a long eyeball” as the cause of long-sightedness.
• Calculating percentage change by dividing by the wrong value.
• Stating “cerebrum controls balance” or “cerebellum controls thought”.
• Giving only a vague ethical remark such as “it is not fair”.
• Writing that nervous tissue can never be repaired, rather than that repair is limited.

Next steps

• Re-read the revision notes and the study guide.
• Tick off statements on the printable checklist and visit the OCR GCSE Biology hub.
• Try the free 10-minute diagnostics to find gaps.
• Book a free trial class if you want help with any of these topics.

Official syllabus

OCR, GCSE (9-1) Gateway Science Biology A (J247), Version 4.0 (August 2026), for first assessment in 2018: statements B3.1d to B3.1h.