Lecture 25

Question 1

What is the chemical nature of lipids?

Answer 1

Hydrophobic or amphiphilic organic molecules

Question 2

What are the three forms of lipid in the diet?

Answer 2

Phospholipid, sterols, triacylglycerol

Question 3

What is an example of a sterol?

Answer 3

Cholesterol

Question 4

What is the role of cholesterol in the body?

Answer 4

A range including membranes, signalling (hormones) and bile salts

Question 5

What is the chemical structure of cholesterol?

Answer 5

A hydrophobic ring structure

Question 6

What is an example of a triacylglycerol (TAGs)?

Answer 6

Fatty acids

Question 7

What is a fatty acid?

Answer 7

Carbon chain to a carboxylic acid

Question 8

What is a free fatty acid (FFA)?

Answer 8

A fatty acid not bound to any other molecule

Question 9

What is the chemical nature of the carbon chain in fatty acids?

Answer 9

Hydrophobic

Question 10

What is the structure of a triagylglycerol?

Answer 10

1x Glycerol (3C) with 3x fatty acids (acyl groups) attached

Question 11

What component of the TAG is polar?

Answer 11

Glycerol

Question 12

What component of the TAG is non-polar?

Answer 12

fatty acid (acyl group)

Question 13

What type of enzyme breaks down TAGs?

Answer 13

Lipase

Question 14

What does lipase do to TAGs?

Answer 14

Hydrolyses it to release the free fatty acids (FFAs)

Question 15

What are bile acids?

Answer 15

Salts synthesised from cholesterol in the liver

Question 16

How are bile acids synthesised?

Answer 16

By adding hydroxyl and/or carboxyl groups to create a hydrophilic face

Question 17

What do bile acids form?

Answer 17

Micelles, multiple bile acids come together to form a hydrophobic core of TAGs inside to be absorbed into epithelial cells