Cholesterol

Question 1

What is cholesterol?

Answer 1

• A type of lipoprotein

- Transported as a lipoprotein due to its insolubility in water

Question 2

What is LDL?

Answer 2

• Low Density Lipoprotein

- ‘bad cholesterol’

Question 3

What is HDL?

Answer 3

• High Density Lipoprotein

- ‘good cholesterol’

Question 4

What can cholesterol be used for?

Answer 4

Making hormones, vitamin D and bile

Question 5

What does LDL do?

Answer 5

• Delivers cholesterol to cells that require it
• Too much LDL can make it build up in arteries
• High cholesterol affects receptor sites in arteries
• Cholesterol forms plaque and narrows arteries
• LDL carries cholesterol to plaque deposits
• Plaque levels increase and can narrow coronary artery and carotid artery

Question 6

What does HDL do?

Answer 6

• Removes plaque and cholesterol deposits from blood

- Returns excess cholesterol to liver where it is removed from the body

Question 7

Define the structure and function of LDLs.

Answer 7

• Triglycerides, from saturated fats, combined with proteins
• Low density so bigger in size
• Bind on receptor sites to be taken up by cell membranes
• High levels of LDLs can affect the sensitivity of receptor sites so that cholesterol is not absorbed easily.
• This can cause atheromas to build up

Question 8

Define the structure and function of HDLs

Answer 8

• Triglycerides, from unsaturated fats, with larger protein component
• High density so smaller in size
• Combine with cholesterol and travels to the liver where it is broken down.
• Lowers cholesterol levels and plaque build up