Question

1. Which of the following is NOT a product of β-oxidation of a 20-carbon fatty acid?

	A.	10 acetyl-CoA
	B.	10 NADH
	C.	9 FADH2

2. Which pathway is NOT active in the liver in the well-fed state?

	A.	glycolysis
	B.	fatty acid synthesis
	C.	glycogenesis
	D.	gluconeogenesis

3. Beriberi is a condition caused by a thiamine deficiency. When analyzing blood samples of an individual with Beriberi, what would you expect to find elevated levels of?

	A.	pyruvate
	B.	glutamate
	C.	malonyl-CoA
	D.	acetyl-CoA

4. Rotenone is a toxin that acts on the electron transport chain. When added to actively respiring mitochondria, the ratio of NADH to NAD⁺ increases while the ratio of FADH₂ to FAD does not change. What component of the ETC does it inhibit?

	A.	Complex I
	B.	Complex IV
	C.	Complex III
	D.	Complex II

Answer 1

1.

Beta oxidation can be defined as catabolic process in which fatty acids are broken down in cytosol.Here 2 carbon units are cleaved off at the beta position of an activated fatty acid.

Beta oxidation of 20 carbon fatty acid produces

- 10 acetyl CoA

- 9 FADH2

- 9 NADH

So from the options 10 NADH is not the product of betaoxidation of 20 carbon fatty acid.

Option B is the answer

2.

During well fed state of the liver

- glucose is stored in liver as glycogen, glycogenesis

- Glucose is converted to acetyl CoA , Glycolysis

- fatty acid sythesis occurs

Gluconeogenesis is the pathway which is not active in liver during well fed state. It is synthesis of sugar from non carbohydrate sources.

Option D is the answer

Gluconeogenesis.

3.

Beriberi is a disease caused by Vitamin B1/ thiamine deficency. The individuals affected with beriberi have high levels of pyruvate and alpha ketoglutarate in blood.

When analyzing blood samples of beriberi patients we can see elevated level of Pyruvate.

Other options are wrong.

Option A is the correct answer.

Pyruvate is the answer.

4.

Rotenone is a toxin which acts on the electron transport chain. It inhibits the transfer of electrons from iron - sulphur in complex 1 to ubiquinone.

Rotenone is inhibitory to Complex I of electron transport chain

Other options are wrong. Rotenone have no inhibitory role in complex II,III,IV.

Option A is the answer.

Complex I is the answer.

.