Question

1- Fatty acyl CoA synthetase catalyses the 2-step fatty acid activation prior to fatty acid synthesis.

True

False

2- Individuals with defects in ammonia clearance tend to suffer neurological problems due to influx of calcium ions into the brain.

True

False

3-Maple syrup disease is largely cause by a defect in the biosynthesis of branched-chain amino acids such as isoleucine.

True

False

4- Uridylylation of PII stimulates the formation of glutamine from glutamate.

True

False

5- Which of the following enzymes catalyzes a highly regulated step involved in both amino acid synthesis and amino acid degradation?

		Alanine aminotransferase
		Aspartate aminotransferase
		Glutamate dehydrogenase
		Glutamine synthetase
		None of the above

6- The binding of CO to hemoglobin causes it to remain in what conformational state?

		Denatured state
		R state
		T state
		Unbound state

Answer 1

Ans .(1) True

The oxidative degradation of fatty acids is a two-step process , catalyzed by acyl CoA synthetase. First, the fatty acid reacts with ATP to form an acyl phosphate. This intermediate reacts subsequently to give acyl-CoA.

Fatty acids are activated in cytosol but oxidation occurs in mitochondria.

Ans .(2) True

Ammonia in brain causes cerebral edema.

The ammonia is responsible for a change in the pH and an increase in calcium.

Ans .(3) True

Maple syrup urine disease is an inborn error of metabolism caused by defects in the branched chain -keto acid dehydrogenase complex, which results in elevations of the branched chain amino acids such as isoleucine in plasma.

Ans .(4) True

Ans .(5) Alanine aminotransferase

Alanine aminotransferase catalyzes the transfer of amino group of alanine to -ketoglutarate.These transamination reactions are reversible and can thus be used to synthesize amino acids from - ketoacids.

Ans .(6) R state

Once Carbon monoxide binds to one site of hemoglobin, hemoglobin turns into the R-state.

Carbon monoxide exerts its toxic effect by stabilizing the R form of hemoglobin.