Lipids

Question 1

Describe the structure of a triglyceride

Answer 1

• glyceol molecule
• 3 fatty acid tails
• 3 ester bonds

Question 2

What state do saturated vs unsaturated triglycerides tend to be?

Answer 2

• sat: solid
• unsat: liquid

Question 3

Why are PLs described as surfactants?

Answer 3

• surface active agents.
• Form a layer on surface of water with phosphate heads in water and tails ticking out.

Question 4

What are sterols

Answer 4

• Steroid alcohols
• Have dual hydrophobic/philic characteristics.
• The OH group is polar therefore hydrophilic. Rest is phobic

Question 5

What is the role of cholesterol in cell membranes?

Answer 5

• Adds stability to cell membranes by keeping them fluid at low temps and preventing them becoming too fluid at high temps

Question 6

What molecules are manufactured from cholesterol?

Answer 6

• vitamin D
• Steroid hormones
• Bile

Question 7

What are the roles of lipids?

Answer 7

• membrane formation
• hydrophobic barriers
• hormone production
• electrical insulation
• waterproofing
• energy storage
• thermal insulation
• cushioning
• buoyancy