Lipids

Question 1

What lipids have energy storage functions?

Answer 1

triacylglycerols

Question 2

What lipids have membrane structural support functions?

Answer 2

phospholipids and sterols

Question 3

What lipids have signal transduction functions?

Answer 3

steroids

Question 4

What are commonly occurring features of fatty acids?

Answer 4

even number of carbon atoms, unbranched, not conjugated, and in cis configuration

Question 5

What saturated fatty acid consists of 12 carbons?

Answer 5

Laurate

Question 6

What saturated fatty acid consists of 14 carbons?

Answer 6

Myristate

Question 7

What saturated fatty acid consists of 16 carbons?

Answer 7

Palmintate

Question 8

What saturated fatty acid consists of 18 carbons?

Answer 8

Stearate

Question 9

What saturated fatty acid consists of 20 carbons?

Answer 9

Arachidate

Question 10

How are lipids in a mixture analyzed?

Answer 10

An organic solvent containing chloroform, methanol, and water is added to the mixtures and the lipids are found with the chloroform and the other polar molecules are found with the methanol/water. Once extracted the lipids can be separated by adoption chromatography.

Question 11

How is fatty acid composition analyzed?

Answer 11

transesterification

Question 12

Describe the process of transesterification.

Answer 12

Fatty acids form ester linkages with methanol, these fatty acids are then separated based on chain length and degree of unsaturation (greater chain length and unsaturation = greater elution time), then more techniques can be used to identify the fatty acids