Lipids Question

Question 1

Describe how a triglyceride molecule is formed.

Answer 1

One glycerol and three fatty acids;

2. Condensation (reactions) and removal of three molecules of water
3. Ester bond(s) (formed)

Question 2

Describe how an ester bond is formed in a phospholipid molecule

Answer 2

Condensation (reaction)
2. Between of glycerol and fatty acid

Question 3

Describe how you would test a piece of food for the presence of lipid.

Answer 3

1-Dissolve in alcohol which is ethanol , then add water
2. White emulsion shows presence of lipid.

Question 4

Scientists investigated the percentages of different types of lipid in plasma membranes from different types of cell. The table shows some of their results.

The scientists expressed their results as Percentage of lipid in plasma membrane by mass. Explain how they would find the values

Answer 4

Divide mass of each lipid by total mass of all lipids (in that type of cell)
2. Multiply answer by 100