16- When the body is deficient in oxaloacetate
a) acetyl CoA from the b-oxdiation pathway cannot enter the citric acid cycle
b) oxaloacetate is diverted to gluconeogenesis
c) acetyl CoA is diverted to form the ketone bodies
d) all of the above are true
e) none of the above
17- The synthesis of ketone bodies involves
a) synthesis of acetoacetyl-CoA by reversal of the thiolase reaction of fatty oxidation
b) synthesis of b-hydroxy-b-methylglutaryl-CoA (HMG-CoA)
c) cleavage of HMG-CoA to acetoacetate.
d) b-Hydroxybutyrate is produced by reduction of acetoacetate.
e) all of the above
18- Which of the statements about ketone body production is FALSE?
a) Ketone bodies are produced when there is more acetyl-CoA in the liver than can be oxidized in the citric acid cycle.
b) Ketone bodies production is not a normal process, and occurs only in diabetes or starvation
c) The ketone bodies produced in the body are the free acids and not the CoA esters.
d) When fatty acid oxidation in the liver is uncontrolled, ketone body production becomes excessive and life-threatening because these acidic compounds lower the pH of blood
e) When fatty acid oxidation
19- In which of the following ways can the 4-carbon compound acetoacetyl CoA produced in fatty acid degradation be further metabolized?
a) It can break down further to form acetyl CoA,
b) It can be converted to the ketone bodies
c) It can be used for synthesis of cholesterol and its many derivÂatives.
d) It can do all of the above
e) It can do none of the above
20- Acetyl CoA from the beta-oxidation pathway cannot enter the citric acid cycle in which of these circumstances?
a) periods of fasting
b) periods of starvation
c) diabetes
d) when the body is deficient in oxaloacetate
e) all of the above
