Lipid Metabolism

Question 1

Two molecules of__________ condense at the diphosphate end to form squalene.

Answer 1

farnesyl diphosphate

Question 2

The formation of cholesterol from lanosterol takes place in the membranes of

Answer 2

the endoplasmic reticulum

Question 3

The double bond at C8´C9 is subse-quently moved to C5´C6 in two steps, forming

Answer 3

desmosterol

Question 4

facilitate the anchoring of proteins into lipoid membranes and may also be involved in proteinprotein interactions and membrane-associated protein trafficking.

Answer 4

Protein prenylation

Question 5

CHOLESTEROL SYNTHESIS IS CONTROLLED BY

Answer 5

REGULATION OF HMG-C oA REDUCTASE

Question 6

responsible for Virtually all plasma Cholesteryl Ester in humans

Answer 6

plasma LCaT

Question 7

Facilitates Transfer of Cholesteryl Ester From hDL to Other Lipoproteins

Answer 7

Cholesteryl Ester Transfer protein

Question 8

Bile acid Synthesis Is regulated at the

Answer 8

CYp7a1 Step

Question 9

HMG-CoA reductase in liver is inhibited by

Answer 9

mevalonate, the immediate product of the reaction, and by cholesterol, the main product of the pathway.

Question 10

regulates the recycling of the receptor to the cell surface by targeting it for degradation.

Answer 10

recent research has shown that the protein proprotein convertase subtilisin/kexin type 9 (PCSK9

Question 11

principal sterol in the feces; it is formed from cholesterol by the bacteria in the lower intestine.

Answer 11

Coprostanol

Question 12

primary bile acids

Answer 12

cholic acid (found in the largest amount in most mammals) and chenodeoxycholic acid

Question 13

first and prin-cipal regulatory step in the biosynthesis of bile acids

Answer 13

7α-hydroxylation of cholesterol by CYP7A1

Question 14

first step is respon-sible for a significant proportion of the primary bile acids syn-thesized.

Answer 14

sterol 27-hydroxylase

Question 15

The primary bile acids (Figure 26–7) enter the bile as glycine or taurine conjugates.
True or False

Answer 15

True

Question 16

the ratio of the glycine to the taurine conjugates is normally

Answer 16

3:1

Question 17

secondary bile acids,

Answer 17

deoxycholic acid, and lithocholic acid.

Question 18

The principal rate-limiting step in the biosynthesis of bile acids is at the

Answer 18

CYP7A1 reaction

Question 19

reduces blood cholesterol levels by inhibit-ing the absorption of cholesterol by the intestine by blocking uptake via the Niemann-Pick C-like 1 protein

Answer 19

Ezetimibe

Question 20

act mainly to lower plasma triacylglycerols by decreasing the secretion of triacylglycerol and cholesterol-con-taining VLDL by the liver

Answer 20

clofibrate, gemfibrozil, and nico-tinic acid,