3.1.3 lipids

Question 1

Triglycerides and phospholipids are two groups of lipid

Answer 1

.

Question 2

Triglycerides are formed by the condensation of one molecule of glycerol (CH2OH) and three molecules of fatty acid

Answer 2

.

Question 3

A condensation reaction between glycerol and a fatty acid (RCOOH) forms an ester bond

Answer 3

.

Question 4

The ‘R’ group of a fatty acid may be saturated or unsaturated

Answer 4

.

Question 5

If something is saturated it has no double bonds

Answer 5

.

Question 6

If something is unsaturated It has either

One double bond between carbon atoms -> monounsaturated

Or

More than one double bond between carbon atoms -> polyunsaturated

Answer 6

.

Question 7

In a phospholipid one of the fatty acids of a triglyceride is substituted by a phosphate containing group so there’s one molecule of glycerol bonded too two fatty acids and then a phosphate contains group

Answer 7

.

Question 8

The different properties of phospholipids and triglycerides relate to their different structures.

Answer 8

.

Question 9

The test for lipids is know as the emulsion test . Ethanol is added to a solution that potentially could contain lipids , the test tube is then shaken and water is added to it , a positive result would be indicated by the formation of a cloudy white suspension , if a negative result occurs the solution will remain colourless.

Answer 9

.