3.1.3 Lipids

Question 1

Compare and contrast the structure and properties of triglycerides and phospholipids

Answer 1

Both contain ester bonds
Both contain glycerol
Fatty acids on both can be saturated or unsaturated
Both insoluble in water
Both contain C,H,O + phospholipids contain P
Phospholipids- 2 fatty acids + phosphate group, triglycerides- 3 fatty acids
Triglycerides- hydrophobic/non-polar, phospholipids- hydrophilic + hydrophobic region

Question 2

Triglyceride structure

Answer 2

3 fatty acids + 1 glycerol
Fatty acids each form ester bond with glycerol by condensation reaction
Fatty acids can be saturated or unsaturated

Question 3

Phospholipid structure

Answer 3

2 fatty acids, 1 phosphate, 1 glycerol
Fatty acid hydrophobic
Phosphate hydrophilic

Question 4

Where do ester bonds form?

Answer 4

Between glycerol molecule and fatty acid

Question 5

Triglycerides functions

Answer 5

Energy storage molecules
Insoluble - don’t affect water potential

Question 6

Phospholipids functions

Answer 6

Make up bilayer of cell membranes
Control what enters + leaves cell
Hydrophobic tail impedes water soluble molecules movement