Exam 2 practice test

Question 1

Which of the following is the best definition of an acyl group?

a. Organic radical derived from an organic acid by the removal of the carboxylic hydroxyl group
b. Reduced Lewis-Fischer base created from oxidative decarboxylation
c. Carboxyl groups removed during oxidation/reduction reactions during beta oxidation
d. Methylene interrupted segment within an unsaturated fatty acid

Answer 1

a. Organic radical derived from an organic acid by the removal of the carboxylic hydroxyl group

Question 2

Which of the following best describes glycogen?

a. Polysaccharide containing only glucose with α 1-4 and α 1-6 bonds
b. Polysaccharide containing only glucose with only α 1-6 bonds
c. Disaccharide containing only glucose connected by α 1-4 bonds
d. Polysaccharide containing glucose & galactose connected by α1-4 bonds

Answer 2

a. Polysaccharide containing only glucose with α 1-4 and α 1-6 bonds

Question 3

High glucagon levels will stimulate which of the following?

a. Acetyl CoA carboxylase
b. Fatty Acid Synthase
c. Glycogen Phosphorylase
d. Phosphofructokinase

Answer 3

c. Glycogen Phosphorylase

Question 4

What molecule is stolen from the Kreb’s Cycle to make glucose during ketosis?

a. Pyruvate
b. Phosphoenolpyruvate
c. Oxaloacetate
d. Isocitrate

Answer 4

c. Oxaloacetate

Question 5

Which of the following would inhibit Acyl-CoA Dehydrogenase?

a. High levels of ATP
b. Low levels of NADH
c. Low Insulin levels

Answer 5

a. High levels of ATP

Question 6

Ketone body formation is stimulated by:

a. Decreased glucagon levels
b. Decreased glucose levels
c. Decreased acetyl levels
d. Increased oxaloacetate levels

Answer 6

b. Decreased glucose levels

Question 7

What is the type of glycosidic bond found within a glycogen chain?

a. Alpha 1,4
b. Alpha 1,2
c. Alpha 1,8
d. Beta 1,2

Answer 7

a. Alpha 1,4

Question 8

Citrate is exported from the mitochondria to begin fatty acid synthesis. Citrate is broken down into
what two products (via citrate lyase)?
a. Isocitrate and Succinate
b. Acetyl CoA and Pyruvate
c. Acetyl CoA and Oxaloacetate
d. Acetyl CoA and Malate

Answer 8

C. Acetyl CoA and Oxaloacetate

Question 9

Which is the correct order of reactions during fatty acid synthesis?

a. Oxidation, reduction, hydration, thiolysis
b. Condensation, reduction, dehydration, reduction
c. Oxidation, hydration, oxidation, thiolysis
d. Condensation, oxidation, hydration, reduction

Answer 9

b. Condensation, reduction, dehydration, reduction

Question 10

Which of the following two amino acids are not glucogenic?

a. Tyrosine and Tryptophan
b. Leucine and Lysine
c. Alanine and Glutamine
d. Aspartate and Asparagine

Answer 10

B. Leucine Lysine

Question 11

What is the alpha keto acid that corresponds to alanine?

a. Oxaloacetate
b. Lactate
c. Pyruvate
d. Alpha ketoglutarate

Answer 11

c. Pyruvate

Question 12

Which of the following amino acids is muscle able to significantly oxidize?

a. Valine
b. Phenylalanine
c. Glycine
d. Lysine

Answer 12

a. Valine

Question 13

In exercising skeletal muscle, which of the following best represents the action of ALT?

a. oxaloacetate + glutamine → aspartate + α ketoglutarate
b. oxaloacetate + glutamate → aspartate + glutamine
c. alanine + pyruvate → aspartate + α ketoglutarate
d. pyruvate + glutamate → alanine + α ketoglutarate

Answer 13

d. pyruvate + glutamate → alanine + α ketoglutarate

Question 14

Which of the following represents AST’s action in the liver?

a. oxaloacetate + alanine → aspartate + α ketoglutarate
b. glutamate + oxaloacetate → aspartate + α ketoglutarate
c. alanine + pyruvate → aspartate + α ketoglutarate
d. glutamate + pyruvate → alanine + α ketoglutarate

Answer 14

b. glutamate + oxaloacetate → aspartate + α ketoglutarate

Question 15

What best represents the action of glutamate dehydrogenase?

a. glutamate + NAD → α ketoglutarate + NADH + NH3
b. glutamate + NAD → ribose + NADPH + NH3
c. oxaloacetate + alanine → glutamate + α ketoglutarate
d. glutamate + oxaloacetate → aspartate + α ketoglutarate

Answer 15

a. glutamate + NAD → α ketoglutarate + NADH + NH3

Question 16

How many nitrogen atoms are contained in one urea molecule?

a. 1
b. 2
c. 3
d. 4

Answer 16

B. 2

Question 17

What two amino acids does skeletal muscle export more than it imports?

a. Tyrosine and Aspartate
b. Glutamate and Aspartate
c. Glutamine and Alanine
d. Leucine and Lysine

Answer 17

c. Glutamine and Alanine

Question 18

During exercise, which of the following is TRUE?

a. Muscle aspartate levels increase and glutamate levels increase
b. Muscle glutamate levels fall and alanine production increases
c. Muscle levels of leucine and valine both increase
d. Muscle glutamate uptake decreases and alanine production decreases

Answer 18

b. Muscle glutamate levels fall and alanine production increases

Question 19

What best describes the function of Aspartate Aminotransferase in the liver?

a. To transfer an amino group from alanine to pyruvate
b. To transfer an amino group from pyruvate to alanine
c. To transfer an amino group from glutamate to oxaloacetate
d. To transfer an amino group from aspartate to pyruvate

Answer 19

c. To transfer an amino group from glutamate to oxaloacetate

Question 20

Cells are rapidly dividing in the gastrointestinal tract. To help meet the needs of cell division, which of
the following will be occurring?
a. Muscle exports glutamate
b. Muscle converts pyruvate to alanine
c. Muscle converts glutamate to glutamine
d. Muscle converts oxaloacetate to aspartate

Answer 20

c. Muscle converts glutamate to glutamine