BSc Biochemistry Sem III 2018 2019 Oct 2019 BIO CHEM BIOCHEMISTRY PAPER I Question Paper - Mumbai University | munotes

Questions asked in this paper

• (ii) Figures to the right indicate full marks

1. Q1 A) Match the following: 4 marks
2. Q1 B) Answer the following: (any three) 9 marks
   • (i) Briefly explain Koshland’s hypothesis
   • (ii) State True or False, giving detailed reasons: “Enzymes are consumed during
   • (iii) Citing examples, explain how pH affects enzyme activity
   • (iv) Differentiate between cofactors, coenzymes and prosthetic group
   • (v) Discuss the advantages of the LB plot
   • (vi) Mention the units of measuring enzyme activity
3. Q1 C) Answer the following in detail: (any two) 12 marks
   • (i) Both enzymes and catalysts hasten the rate of reaction, however there exists dissimilarities between them. Explain the same
   • ii) Write a note on competitive inhibition of enzymes, with suitable examples
   • iii) Given an enzyme with a Km = 10 mM and Vmax= 100 mmol/min. Calculate Vo, if Which will increase the velocity more: a 10-fold decrease in Km, or a 10-fold increase in Vmax?
   • iv) Elaborate on the EC classification of enzymes
4. Q2 A) State True or False:
   • (i) IAA is produced in actively growing fruits
   • (ii) Hormones are secreted by ductless glands
   • (iii) Progesterone is secreted by corpus luteum
   • (iv) Epinephrine binds to intracellular receptor
5. Q2 B) Answer the following: (any three) 9 marks
   • (i) Briefly explain the different types of hormonal receptors
   • (ii) Discuss the physiological significance of FSH
   • (iii) State true or false giving detailed reasons- Fast acting hormone generally
   • (iv) Mention any three functions attributed to cytokinins
   • (v) Describe how apical dominance is an important effect of auxin
   • (vi) With a suitable example, explain the significance of secondary messenger
6. Q2 C) Write informative notes on: (Any two) 12 marks
   • i) Physiological role of thyroxine
   • ii) Ethylene as a phytohormone
   • Q. P. Code: 20779
   • iii) Hierarchial organization of mammalian endocrine system
   • iv) Vasopressin
7. Q3 A) State True or False: 4 marks
   • (i) Buffers are mixtures of strong acid and weak base
   • (ii) The flat zone in a titration curve is the transition zone
   • (iii) Phosphate buffer is the major intracellular buffer
   • (iv) The equilibrium constant of water is 1.8 X
8. Q3 B) Attempt: (any three) 9 marks
   • (i) What is the pH of a mixture of 0.062 M NaH2PO, and 0.088 M
9. Q4 Define: Buffer; Kw and pHm
   • (iii) Draw structures of the predominant ionization states of Glycine
   • (iv) With the help of structure explain zwitterion. In which direction will it move when subjected to an electric field?
   • (v) Citing example of acetate buffer, explain buffering capacity
   • (vi) Calculate the concentration of hydrogen ion, if the pH of the solution is 4.6?
10. Q3 C) Answer the following in detail: (any two) 12 marks
    • (i) Explain the role of hemoglobin as blood buffer
    • (ii) Derive the relationship between pH and pKa of a weak acid. Also, explain its
    • (iii) With ionization forms and pKa values, explain the titration curve of an acidic amino acid with a standard alkali
    • (iv) Justify: “The value of neutral pH as 7 is not an arbitrarily chosen value.” Also, calculate the OH- concentration in a neutral solution, if the value of Kw
11. Q4 A) Define the following: (any five) 10 marks
12. Q4 B) Answer the following: (any three) 15 marks
    • (i) Justify: “Bicarbonate buffer system is the most important extracellular
    • (ii) Explain Sorenson formal titration and state its significance
    • (iii) Compare and contrast: Auxins and Gibberellins
    • (iv) Explain the sequence of events that takes place when epinephrine binds to
    • (v) Discuss the various factors affecting enzyme activity
    • (vi) What is Km of an enzyme? How will the Km of succinate dehydrogenase be affected at: (a) (b) = Vmax/2 (c) In presence of Malonate

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