Chapter 10

Question 1

What are the carbon skeleton, melting point and number of double bonds for Palmitic acid?

Answer 1

16:0, 63.1*C, 0 double bonds (16:0)

Question 2

What are the carbon skeleton, melting point and number of double bonds for Stearic acid?

Answer 2

18:0, 69.6*C, 0 double bonds (18:0)

Question 3

What are the carbon skeleton, melting point and number of double bonds for Arachidic acid?

Answer 3

20:0, 76.5*C, 0 double bonds (20:0)

Question 4

What are the carbon skeleton, melting point and number of double bonds for Lignoceric acid?

Answer 4

24:0, 86*C, 0 double bonds (24:0)

Question 5

What are the carbon skeleton, melting point and number of double bonds for Palmitoleic Acid?

Answer 5

16:1 (delta 9), 1 to -0.5*C, 1 double bond at C9

Question 6

What are the carbon skeleton, melting point and number of double bonds for Oleic acid?

Answer 6

18:1 (delta 9), 13.4*C, 1 double bond at C9

Question 7

What are the carbon skeleton, melting point and number of double bonds for Linoleic acid?

Answer 7

18:2, (delta 9, 12), 1-5*C, 2 double bonds (one at C9, the other at C12)

Question 8

What are the carbon skeleton, melting point and number of double bonds for alpha-Linoleic acid?

Answer 8

18:3 (delta 9, 12, 15), -11*C, 3 double bonds (one at C9, C12, and C15)

Question 9

What are the carbon skeleton, melting point and number of double bonds for Arachidonic acid?

Answer 9

20:4 (delta 5, 8, 11, 14), -49.5*C, 4 double bonds

Question 10

What is the makeup of triacylglycerol?

Answer 10

Glycerol backbone with C1, C2, and C3 are hydroxyl groups esterified with three fatty acid side chains.

Question 11

Explain the makeup of glycerophospholipids

Answer 11

Glycerol backbone. C1 and C2 are hydroxyl groups esterified with fatty acid side chains. C1 is usually saturated (C16 or C18). C2 is unsaturated (C18 or Arachidonic acid). Phosphorylated alcohol on C3.

Question 12

Explain the makeup of sphingolipids.

Answer 12

The first three carbons at the polar end of sphingosine are analogous to the three carbons of glycerol in glycerophospholipids. The amino group at C-2 bears a fatty acid in amide linkage. The fatty acid is usually saturated or monounsaturated, with 16, 18, 22, or 24 carbon atoms. Ceramide is the parent compound for this group. Other sphingolipids differ in the polar head group (x) attached at C-1. Gangliosides have very complex oligosaccharide head groups.

Question 13

What can phospholipases do?

Answer 13

They can process phospholipids.

Question 14

What are the four main phospholipases talked about in class?

Answer 14

Phospholipase A1, Phospholipase A2, Phospholipase C and Phospholipase D

Question 15

What is important about Phospholipase A2?

Answer 15

It works at the C2 (which is often Arachidonic acid). It is the rate-limiting step for production of eicosanoids.

Question 16

What does eicos mean?

Answer 16

Eicos=20

Question 17

How are eicosanoids/prostanoids in terms of structure?

Answer 17

They are all derived from Arachidonic acid.

Question 18

What increases production of eicosanoids/prostanoids?

Answer 18

Increased by increased phospholipase A2 activity.

Question 19

What is the function of eicosanoids/prostanoids?

Answer 19

Collectively they mediate inflammatory responses (e.g. pain, fever), local blood pressure, blood clotting, possibly the onset of labor, possibly sleep/wake cycles.

Question 20

How are eicosanoids/prostanoids synthesized?

Answer 20

Various enzymes convert arachidonic acid into prostaglandins or thromboxane or leukotrienes; the first two by COX (cyclooxygenase). Leukotrienes are not produced by COX

Question 21

What is the most abundant phospholipid in the cell membrane?

Answer 21

Phosphocholine