A cataract is a defect of the eye.
The Table shows the percentage of people with cataracts in different age groups.
Table
| Age group in years | Percentage of people with cataracts |
|---|---|
| 40 to 49 | 2.5 |
| 50 to 59 | 6.8 |
| 60 to 69 | 20.0 |
| 70 to 79 | 42.0 |
| 80 and over | 68.0 |
Describe the relationship between age and the percentage of people with cataracts.
A town has 2400 people aged 70 to 79.
Use the Table to estimate the number of these people who have cataracts.
A cataract can make colours look faded.
Suggest why.
Describe how a cataract is corrected.
42 exam-style questions on Edexcel GCSE Biology 2.4 The eye, covering 2.4.1 Structure and function of the eye and 2.4.2 Eye defects and their correction. Each one has a worked solution and a mark scheme showing where the marks go.