Medical Biochemistry — DU B. Sc. (Hons) Biomedical Previous Year Question Papers

(iii) Molecule that regulates hunger between the meals of the day. (vi) Target organ of leptin. (v) Enzyme that is of diagnostic significance in myocardial infarction. 5. (a) Give the complete biochemical reaction catalysed by LDH. Which are different isoforms. Discuss the diagnostic significance of the enzyme. 5 (b) During fasting, how does a shift in metabolism provide fuel for the brain? 5 (c) Discuss the metabolism of Vitamin D in the body. What is its target organ? 5 6. (a) Why is HDL called good cholesterol? Illustrate and discuss the process of reverse cholesterol transport? 8 (b) Discuss the source, target organ and mechanism of action of leptin. 7 (c) Subparts of the questions should be attempted together. (d) Draw illustrations or diagrams wherever necessary. (iii) Vitamin (b) Differentiate between 3×4=12 (ii) Brown Adipose Tissue and White Adipose Tissue (c) State true or false and justify: 2.5×4=10 (i) Hemolytic anemia may occur in premature and low birthweight infants. (ii) Neuraminidases are target of anti-viral drug (iii) Chylomicrons have cholesterol esters as well as free cholesterol. (vi) ALT is a more liver specific enzyme. 2. Write short notes on 5+5+5=15 (b) Folate Trap 3. (a) Name the enzyme that catalyses/takes part in the following reactions (i) Carboxylation of glutamate residues in proteins that bind Caft (ii) Transamination reactions (iii) Activity of proto-collagen hydroxylase (vi) Activity of methyl malonyl CoA mutase (v) Redox reactions in various metabolic pathways (b) Give the reaction catalysed by SGOT or SGPT. What role does pyridoxal phosphate play in this reaction? (c) How is cholesterol synthesis regulated at the transcriptional level? 5+5+5=15 4. (a) Discuss the clinical significance and biochemical metabolic reactions catalysed by creatin kinase. Why do muscle builders take creatine supplements? 5 (b) Metabolism of the brain is remarkable in several ways. Elucidate. 5 (c) Give one word for 5 (i) Precursor lipid of the prostaglandins and leukotrienes. (ii) Enzyme inhibited by the statins.