1.2 - Lipids

Question 1

Name the two groups of lipid

Answer 1

Triglycerides and phospholipids

Question 2

How are triglycerides formed?

Answer 2

Condensation of 1 glycerol molecule and 3 fatty acid molecules

Question 3

How is an ester bond formed?

Answer 3

Condensation reaction between glycerol and fatty acid

Question 4

Name the components of a phospholipid

Answer 4

One phosphate, one glycerol, two fatty acids

Question 5

Describe the emulsion test for lipids

Answer 5

Add ethanol then add water and shake
White/ milky emulsion

Question 6

Function of triglycerides

Answer 6

Energy release - energy stored in fatty acid hydrocarbon tails
Repel water - hydrophobic fatty acid tails so don’t affect water potential
Lipid droplets

Question 7

Function of phospholipids

Answer 7

Hydrophilic - interacts with water
Hydrophobic - repels water
Controls what passes through plasma membrane

Question 8

What is a saturated fatty acid?

Answer 8

Has only C-C bonds in hydrocarbon chain

Question 9

What is an unsaturated fatty acid?

Answer 9

Has at least one C=C bond in hydrocarbon chain