IGNOU BCHET-149 December 2022 Previous Year Question Paper

Q1.(a) Why are’ mitochondria called the powerhouses of cells ? Explain the role of mitochondrial matrix in living cells. 5

(b) Explain the formation of anomers in carbohydrates taking a monosaccharide as an example.

Q2.(a) Explain the formation of a peptide bond and also explain its stereochemistry. 5

(b) What are lipoproteins ? Draw a generalised structure of a lipoprotein.

Q3.(a) Differentiate between any two of the pairs given below : 5 @) DNA and RNA

(ii) Nucleosides and Nucleotides

(ii) rRNA and mRNA

(b) List the different ways of drug action on human body and describe any one.

Q4.(a) Write the steps involved in an enzyme catalysed reaction. Also write the general reaction for each step. 5

(b) Why is TCA cycle called the amphibolic pathway ? Explain giving examples.

Q5.(a) What is Metabolism ? Describe the convergent and divergent nature of metabolism. Illustrate your answer. 5

(b) What is rancidity of oils ? How is it assessed ? Differentiate between rancidity and saponification number.

Q6.(a) Name the disaccharide which is non- reducing in nature. Write the reason of this behaviour of the disaccharide. 5

(b) What is gluconeogenesis ? Explain the energetics involved in this process.

Q7.(a) Describe the inter-relationship among the three main metabolic pathways involving lipids, carbohydrates and proteins. 5

(b) Write short notes on any two of the following : 5 @) Electron transport chain

(i) Substrate level phosphorylation @ii) Fractionation of subcellular organelles @) DNA at RNA

(ii) RNA 7 mRNA [

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