Biochemistry Previous Year Question Papers

Glycolysis is the only source of energy for the following organ a) Brain b) RBC c) Heart d) Skeletal muscle

The rate limiting step in cholesterol biosynthesis is a) Squalene synthetase c) Mevalonate kinase b) HMG-CoA reductase d) Ketoacyl reductase

The lipoprotein which donates the apoproteins apo CII and apo E to other lipoproteins is a) LDL b) VLDL c) HDL d) Lp(a)

A patient presented with large yellow tonsils, hepatosplenomegaly, corneal opacity and neuropathy.He most probably suffers from a) Abetalipoproteinemia c) Primary Familial hypercholesterolemia b) Tangier’s disease d) Wolman’s disease

The liver cannot utilize ketone bodies due to lack of the enzyme a) Thiolase b) Thiophorase c) Thioesterase d) All of the above

Glycine is involved in the following metabolic pathways 1) Glycine, glutamate and cysteine together form glutathione 2) It is used in the salvage pathway of synthesis of pyrimidines 3) Combines with succinyl CoA resulting in formation of heme 4) Used for conjugation of bile acids to produce bile salts a) 1, 2, 3 b) 1, 3, 4 c) 2, 3, 4 d) 1, 2, 4

The following statements regarding urea cycle are true 1) Urea cycle occurs both in mitochondria and cytosol 2) The non-protein amino acid involved in urea cycle is arginosuccinate 3) The compound linking urea cycle to citric acid cycle is ornithine 4) N- Acetyl glutamate is allosteric activator of Carbamoyl phosphate synthetase I a) 1 & 2 b) 2 & 3 c) 1 & 4 d) 3 & 4

Regarding the products formed from tryptophan, the following is true 1) Melanin, epinephrine & nor-epinephrine are formed from tryptophan 2) Serotonin is 5- Hydroxy tryptamine and is an antidepressant 3) Melatonin is produced by the argentaffin cells of the GIT 4) 60 mg of tryptophan is used to synthesize 1 mg of nicotinic acid a) 1 & 3 b) 3 & 4 c) 2 & 4 d)1 & 2

Pyridoxal phosphate is a coenzyme for the following reactions 1) Transamination 2) Decarboxylation 3) Hydroxylation 4) Redox reactions a) 1 & 2 b) 1 & 3 c) 1 & 4 d) 3 & 4

Which of the following statements about vitamin E are correct 1) Vitamin E is a chain breaking antioxidant 2) Selenium has sparing effect on the dietary requirement of Vitamin E 3) It favours lipid peroxidation in biological membranes 4) It causes hemolysis of RBCs a) 1 & 2 b) 1 & 3 c) 2 & 4 d) 3 & 4