Exam II - Cholesterol

Question 1

T/F Cholesterol is an essential part of cell membranes.

Answer 1

True.

Question 2

Choose the correct answer:

Cholesterol forms loose cross-links and reduces/increases cell membrane fluidity.

Answer 2

reduces

Question 3

What is a cholesterol ester?

Answer 3

the combination of cholesterol and fat to form a long chain fatty acid (LCFA)

Question 4

What is an ester?

Answer 4

Any organic molecule produced by combining an acid with an alcohol

Question 5

What is the primary site for cholesterol synthesis?

Answer 5

the liver

Question 6

T/F Only liver cells can make cholesterol

Answer 6

False, most human cells can make cholesterol.

Question 7

Where in the cell is cholesterol synthesized?
A. Cytosol
B. Mitochondria

Answer 7

A.

Question 8

What is the first unique molecule in cholesterol synthesis? 
A. HMG-CoA
B. Acetoacetyl-CoA
C. Mevalonic acid
D. HMG-CoA reductase

Answer 8

C.

Question 9

What is the main enzyme in cholesterol synthesis? 
A. HMG-CoA synthase
B. Acetoacetyl-CoA thiolase
C. Mevalonic acidase
D. HMG-CoA reductase

Answer 9

D.

Question 10

Which three things are considered the "recipe" for cholesterol synthase? 
A. NAPH
B. ATP
C. Acetyl CoA
D. Water

Answer 10

A, B, C.

Question 11

T/F HMG CoA reductase is irreversible.

Answer 11

True.

Question 12

What is another name for bile salts?

Answer 12

bile acids

Question 13

What is the primary location for bile acid production?

Answer 13

liver

Question 14

What is the secondary location for bile acid production?

Answer 14

intestine

Question 15

Which of the following should you never choose on a Biochem II exam?
A. HMG-CoA reductase
B. cholesterol breakdown/degradation
C. Mevalonate

Answer 15

B.

Question 16

T/F Cholesterol and fat synthesis pathways can run simultaneously.

Answer 16

True.

Question 17

Which of the following is NOT a bile salt?
A. Glycholic Acid
B. Taurocholic Acid
C. Deoxycholic Acid
D. Lithocholate
E. Pentanoic Acid

Answer 17

E. All bile salts/acids end in -olic or -cholate.

Question 18

What is the precursor for bile salts?

Answer 18

cholesterol

Question 19

What is the precursor for all steroid hormones?
A. Pregnenolone
B. Progesterone
C. Androstenedione
D. Esterone

Answer 19

A.

Question 20

List four things that stimulate cholesterol synthesis.

Answer 20

ATP
NADH
Insulin
Fructose

Question 21

List four things that inhibit cholesterol synthesis.

Answer 21

ADP
AMP
NAD
Glucagon