Chapter 17- Lipid II Phospholipids, Glycosphingolipids, And Cholesterol

Question 1

What lipids have an essential role in the synthesis of plasma lipoproteins?

Answer 1

phospholipids and glycosphingolipids

Question 2

what lipids function in transduction of messages from cell surface receptors to secondary messengers that control cellular processes?

Answer 2

phospholipids and glycosphingolipids

Question 3

What lipids function as surfactant?

Answer 3

Phosphatidylcholine

Question 4

Cholesterol is the precursor of what?

Answer 4

bile acids, steroid hormones, 7-dehydrocholesterol

Question 5

A ceramide is composed of?

Answer 5

LCFA attached to amino group of sphingosine

Question 6

a sphingomyelin is composed of?

Answer 6

ceramide and phosphorylcholine

Question 7

Synthesis of phosphatidylcholine requires what nuclei acid?

Answer 7

cytidine triphosphate

Question 8

accumulated sphingomyelin characterized as?

Answer 8

Niemann-Pick disease

Question 9

cerebrosides formed from?

Answer 9

ceramide and UDP-sugars

Question 10

accumulation of cerebrosides characterized as?

Answer 10

Gaucher’s, Krabbe’s disease

Question 11

Sulfatides formed from?

Answer 11

addition of sulfate group to cerebrosides

Question 12

accumulation of sulfides characterized as?

Answer 12

metachromatic leukodystrophy

Question 13

Gangliosides formed from?

Answer 13

cerebrosides by addition of sugars

Question 14

accumulation gangliosides characterized as?

Answer 14

GM1 gangliosidosis, Tay-Sachs disease

Question 15

What toxin inhibits sphingolipid synthesis?

Answer 15

fumonisin

Question 16

What is an important constituent of the myelin sheath of nerve fibers?

Answer 16

sphingomyelin

Question 17

Enzyme deficient in Tacy-Sachs disease?

Answer 17

Hexosaminidase A

Question 18

Enzyme deficient in Fabry’s disease?

Answer 18

alpha-galactosidase

Question 19

Enzyme deficient in Metachromatic leukodystrophy?

Answer 19

arylsulfatase A

Question 20

Enzyme deficient in Krabbe’s disease?

Answer 20

beta-galactosidase

Question 21

Enzyme deficient in Gauchers disease?

Answer 21

beta-glucosidase

Question 22

Enzyme deficient in Niemann-Pick disease?

Answer 22

sphingomyelinase

Question 23

Enzyme deficient in Farber’s disease?

Answer 23

ceramidase

Question 24

What tissues have the largest contribution of cholesterol synthesis?

Answer 24

liver, intestine, adrenal cortex, reproductive tissues

Question 25

biosynthesis of mevalonate occurs where?

Answer 25

cytosol

Question 26

Where are carbons that form cholesterol derived from?

Answer 26

all C's from acetate

Question 27

What molecule provides reducing equivalents for cholesterol synthesis?

Answer 27

NADPH

Question 28

Reactions from mevalonic acid to cholesterol contain how many carbons at each reaction?

Answer 28

mevalonic acid: 6C's -> 6C's -> 5C's -> 5C's -> 10C's -> 15C's -> 30C's -> 30C's -> cholesterol: 27C's

Question 29

If bile acids are increased this is indicative of what disease?

Answer 29

hepatocellular disease or obstructive jaundice

Question 30

Bile salt that is toxic, can cause hemolysis & fever

Answer 30

Lithocholic acid

Question 31

Symptoms of hyperbile acidemia

Answer 31

pruritus, steatorrhea, hemolytic anemia, further injury liver injury

Question 32

What is cholelithiasis?

Answer 32

gallstones, precipitation of cholesterol in bile

Question 33

What is lithogenic?

Answer 33

(stone forming) mole ratio of bile salts & PLs to cholesterol is less than 10:1

Question 34

What is used to convert phosphatidylethanolamine to phosphatidylcholine?

Answer 34

3SAM -> 3SAH

Question 35

glycerol 3-phosphate to phosphatidic acid?

Answer 35

2 fatty acyl-CoA -> 2 CoA-SH