cataracts
Definition
A cataract is a clouding of the lens in the eye that makes it hard to see.
The lens is made up of protein fibres that are arranged in a specific way.
As people age, the protein fibres can start to break down and clump together. This can cause the lens to become cloudy and opaque.
Cataracts can also be caused by injury, inflammation, or exposure to certain chemicals.
There are two main types of cataracts: nuclear cataracts and cortical cataracts. Nuclear cataracts are the most common type of cataract. They occur when the protein fibres in the centre of the lens break down and clump together. This makes the lens become cloudy and opaque. Cortical cataracts occur when the protein fibres in the outer part of the lens break down and clump together. This makes the lens become cloudy and opaque.
Cataracts can be treated with surgery. During surgery, the cloudy lens is removed and replaced with a clear artificial lens. Cataract surgery is a safe and effective procedure that can restore vision.
How can the word be used?
A surgical procedure to remove a cataract.
Different forms of the word
Noun.
Singular: cataract.
Plural: cataracts.
Adjective.
Cataract: relating to or affected by cataracts.
Etymology
The word "cataract" comes from the Latin word "cataracta", which means "waterfall". The Latin word "cataracta" is derived from the Greek word "καταράσσω" (katarrásso), which means "to dash down".
Question
What happens if you have cataracts?
AQA Science Exam Question and Answer
Question:
What are "cataracts," and how do they affect the human eye?
Answer:
"Cataracts" are a medical condition characterised by the clouding of the eye's natural lens, leading to impaired vision.
Cataracts develop when proteins in the eye's lens clump together, causing the lens to become cloudy. This clouding obstructs the passage of light through the lens, leading to blurry or distorted vision. People with cataracts may experience difficulties in activities such as reading, driving, and recognising faces. Cataracts can progress over time, worsening vision if left untreated. However, cataract surgery is a common and effective procedure to replace the cloudy lens with an artificial one, restoring clear vision for the affected individual.