Loading…
Loading…
GCSE Biology · key term
Clouding of the eye’s lens that makes vision blurred or hazy.
Used by Edexcel and OCR
Specification 2.16B, 2.17B · Paper 1
A condition in which the normally transparent lens becomes cloudy, causing blurred or misty vision.
Revise: Eye DefectsIn a cataract, changes in the lens make it cloudy and less transparent. Light no longer passes through the lens clearly, producing blurred or misty vision.
A clouding of the eye’s lens that reduces the light reaching the retina and makes vision blurred.
A cataract makes the lens less transparent. It is not a focusing defect caused by the image forming in front of or behind the retina.
Do not confuse a focusing defect with a cataract: a corrective lens changes the path of light, whereas cataract treatment replaces the cloudy eye lens.
Create a free account to read GCSE Biology revision notes for your exam board and track your progress.
Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Higher), Paper 4 (Higher)
Revise: Eye DefectsA cataract is different from short- or long-sightedness. The eye’s lens becomes cloudy, so light does not pass through it clearly and vision becomes hazy. Changing the focus with glasses does not remove that cloudiness.