Lipids

Question 1

What are lipids?

Answer 1

• macromolecules that contain the element carbon, hydrogen, oxygen and phosphorus

Question 2

What are triglycerides composed of, what is the bond and how does it form?

Answer 2

• triglycerides are composed of a glycerol molecule and three fatty acids.
• OH from the carboxylic function group of fatty acid and H from alcohol function group of glycerol to form ester bond
• condensation reaction
• removal of water

Question 3

What are the uses of triglycerides

Answer 3

• storage of high amounts of energy
• waterproofing
• electrical insulation

Question 4

What are the uses of lipids in general?

Answer 4

• buoyancy
• formation of phospholipid bilayer
• hormone production
• thermal insulation
• cushioning and protection for vital organs

Question 5

What are the uses of cholesterol

Answer 5

• manufactores cholesterol
• produces hormones
• forms part of the bile
• produces vitamin D

Question 6

What is the test for lipids?

Answer 6

• the emulsion test
• add ethanol to sample
• add water and shake
• leave sample
• if cloudy white layer of emulsion form at the top, lipids are present

Question 7

What is the difference between saturated and unsaturated fats?

Answer 7

• unsaturated has double bonds in the hydrocarbon fatty acid chain.
• double bond will cause molecule to kink or bend meaning the atoms aren’t as close together
• unsaturated fats are usually oils
• saturated fats have no double bonds present