Cholesterol Transport & Metabolism

Question 1

why do humans need cholesterol?

Answer 1

synthesis of:

Cell membranes - stabilising and transport.
Steroid hormones - adrenal & sex hormones.
Bile acids - facilitate GIT absorption of dietary fat.

Question 2

What are the sources of cholesterols?

Answer 2

Exogenous - dietary supple such as eggs and shell fish

Endogenous - synthesis in organs and tissues - liver, ovaries, adrenals, intestines, skin.

Question 3

How is cholesterol transported?

Answer 3

transported as water soluble lipoprotein particles.

Question 4

What is the inner fatty/hydrophobic core consist off?

Answer 4

• Cholesterol/ cholesterol esters.
• Triglycerides/ free fatty acids.

Question 5

What is the outer hydrophilic coat consist of?

Answer 5

• Apolipoproteins
• Phospholipid.
• cholesterol.

Question 6

What are the key functions of Apolipoproteins?

Answer 6

• Lipoproteins assembly and transport.
• Maintenance of structural integrity of lipoproteins.
• Enzyme activation and inhibition.
• Cellular receptor binding.

Question 7

What are the 3 major pathways of plasma lipid transport?

Answer 7

• Exogenous intestinal pathway.
• Endogenous hepatic pathway.
• Reverse cholesterol transport.

Question 8

Why are the pathways co-ordinated by the liver?

Answer 8

to ensure maintenance of balance of major lipid classes.