Lipids

Question 1

Name and Explain 4 function of lipids

Answer 1

Energy store - Can be broken down and used as a source of energy in respiration.Good for storage as insoluble in water. Higher energy value per g than carbohydrate.

Insulation

Protection - fat stored around major organs

Phospholipids - make cell membranes

Question 2

What are the 2 types of lipids?

Answer 2

Triglycerides

Phospholipids

Question 3

How is a Triglyceride formed?

Answer 3

Condensation between glycerol + 3 fatty acids forming an ester bonds

Question 4

What are saturated fatty acids

Answer 4

All the bonds between the carbons in the hydrocarbon chain are single bonds and there is the max No. Of hydrogen atoms

Question 5

What are unsaturated fatty acids

Answer 5

Some of the bonds between the carbons in the hydrocarbon chain are double bonds. Lower melting points

Question 6

What does Hydrophyllic mean?

Answer 6

‘water loving’ - phosphate attracts water

Question 7

What does Hydrophobic mean

Answer 7

‘water hating’ - fatty acids repel water

Question 8

Test for Lipids?

Answer 8

Dissolve the sample in ethanol and pour this into a test tube of water. A cloudy white emulsion indicates that the lipid is present.