Mock Exam 2

Question 1

Very long chain fatty acids are degraded in the______________
in the ______________

Answer 1

Peroxisomes; mitochondria

Question 2

Which of the following would be the best clinical indicator for a diagnosis of X-linked * adrenoleukodystrophy.

Answer 2

High C26:C22 ratio

Question 3

HMG-CoA lyase deficiency prevents the formation of what important type of fuel molecules?

Answer 3

Ketone Bodies

Question 4

Which step is not required for transport of fatty acids into the mitochondria once they enter the cell
a. Attachment to CoA-SH with ATP consumption
Attachment to carnitine
Transfer from carnitine to COA-SH
Oxidation by FAD
е.
Facilitated diffusion of acyl carnitine by a translocase

Answer 4

Oxidation by FAD

Question 5

Which step in the TCA resembles the acyl Co dehydrogenase in B-oxidation??
a. fumarase (b,
Succinyl CoA synthetase
c. Succinate dehydrogenase
d. Malate dehydrogenase
e. a-ketoglutarate dehydrogenase

Answer 5

c. Succinate dehydrogenase

Question 6

You suspect an individual has a metabolic defect in fat metabolism, so you do a series of clinical tests on the individual and find elevated levels Acyl-CoA in the cytosol of liver and muscle cells and reduced level of carnitine in the blood. What is the most likely defect in this individual.
(o.
a. Acyl CoA synthetase (Fatty acid thiokinase) +
Carnitine Acyl transferase I
C.
Carnitine Acyl transferase II
d.
Translocase (Carnitine transporter)
• Organic Cation transporter 2 (OCTN2),

Answer 6

Organic Cation transporter 2 (OCTN2),

Question 7

Which of the following steps does occur in B-oxidation of a fatty acid.

Answer 7

B. a dienoy1-CoA is reduced to an enoyI Cos
c. a ketoacyl Cod cleaved by COA-SE
d. a hydroxyacyl-CoA is oxidized to a ketone @. An acyl Cod is oxidized by FAD

Question 8

In the electron transport chain, Complex I catalyzes what overall reaction
a. NADH + cytochrome Cox - NAD* + Cytochrome Cred
b. NADH + 02 - NAD* + H20
c. NADH + Q + NAD* + QH2
d. FADH2 + Q -> FAD + QH2
e. NAD+ + Q + NADH + 0H2

Answer 8

© NADH + Q + NAD* + QH2

Question 9

About how long after a meal to chylomicrons remain in circulation?
a. 5-10 min
b.1-2 hours
c. 4-6 hours
(d. 10-12 hours
e. Around 24 hours

Answer 9

1-2 hours

Question 10

Which of the following compounds stimulates fat metabolism by activating the acetyl-CoA carboxylase?

Answer 10

Citrate

Question 11

In Systemic Carnitine deficiency, which of the following is not a contributing factor to the increased
levels of fat stored in the liver?
a. Hormonal stimulation of lipases in adipose tissue
b. Decrease in 3-oxidation of fatty acids in liver
c. Increased formation of ketone bodies
d.
Reduction in blood glucose levels
e. Increased TAG formation in liver cells

Answer 11

Increased formation of ketone bodies

Question 12

The OCTN2 transporter that is deficient in systemic carnitine deficiency is found in
a. Muscle and liver, but not kidney
b. Muscle and kidney, but not liver
c. Kidney and lung, but not muscle )kidney and liver, but not muscle
c. kidney and lung, but not muscle

Answer 12

b. Muscle and kidney, but not liver

Question 13

Which complex in the electron transport chain transfers electrons from Q112 to cytochrome c?
a. Complex I
b. Complex II
c. Complex III
d. Complex IV
e. Complex V

Answer 13

c. Complex III

Question 14

This enzyme is present in peroxisomes but not mitochondria and is involved in B-oxidation;
a. Catalase
b. NADPH oxidase
c. Acyl-CoA dehydrogenase
d. Thiolase
e. Acyl CoA oxidase

Answer 14

Acyl CoA oxidase