LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
B.Sc. DEGREE EXAMINATION –PLANT BIOLOGY & PLANT BIO-TECH.
SUPPLEMENTARY EXAMINATION – JUNE 2007
PB 5403 - PLANT BIO-CHEMISTRY
Date & Time: 27/06/2007 / 9:00 - 12:00
Dept. No.
Max. : 100 Marks
PART A
(20 marks)
Answer All questions
I Choose the Correct Answer
( 5 x 1 = 5 marks)
01. Which technique is used to estimate the concentration of biochemical compound in a
solution.
a. colorimeter b. centrifuge
c. chromatography
d. pH
02. The α – carbon in all amino acids is asymmetric except ….
a. proline
b. serine
c. glycine
d. glutamine
03. Which of the following one is a non reducing sugar?
a. glucose
b. fructose
c. maltose
d. sucrose
04. The lipid containing a fatty acid, carbohydrate and nitrogen base is called …
a. phospholipids b. waxes
c. fats and oils
d. glycolipids
05. The multiple forms of an enzyme catalyzing the same reaction are ………
a. holoenzymes b. isoenzymes
c. co enzymes
d. allosteric enzymes
II State whether the following statements are True or False
( 5 x 1 = 5 marks)
06. Native gel is used to isolate enzymes.
07. Starch is a homopoloysaccharide.
08. The dipeptide contains one peptide bond.
09. Saturated fatty acids contain double bond.
10. IUB refers to International Union of Biochemistry.
III. Complete the following
( 5 x 1 = 5 marks)
11. Transfer of one or more electrons from one atom to another is referred to as …..
12. A carbon is said to be asymmetric when it is attached to …. different atoms or
groups.
13. The bond forming the backbone of protein structure is …….
14. The site at which substrate binds with an enzyme is called ….
15. The nitrogen base present in lecithin is ………
IV. Answer all, each in about 50 words
16. Define biomolecules
17. What are D and L – isomers?
18. What is peptide bond?
19. Distinguish between phospho and glycolipids.
20 What is allosteric enzyme?
( 5 x 1 = 5 marks)
PART B
( 5 x 8 = 40 marks)
Answer any five, each within 350 words only. Draw diagrams and flowcharts wherever necessary.
21. Discuss the basic principle and types of chromatography.
22. Describe the structure of polysaccharides in plants.
23. What biological functions do proteins perform?
24. Explain the working principle and types of centrifuge.
25. Describe the classification of enzymes.
26. Give a brief account of oxidation of fatty acids.
27. Write notes on coenzymes.
28. Explain the chemical bonds involved in protein structure.
PART C
( 2 x 20 = 40 marks)
Answer the following, each within 1500 words only. Draw diagrams and flowcharts wherever
necessary.
29. a) i. With suitable diagram, describe SDS-PAGE. (10 marks).
ii. Explain in detail the types of gel used in electrophoresis. (10 marks)
Or
b) Give an account of:
i. pectin. (5 marks)
ii. classification of amino acids (15 marks)
30. a) i. Define active site. Explain the mechanism of enzyme action (8 marks).
ii. Define enzyme inhibition. Explain the types of enzyme inhibition. (12 marks)
Or
b) i. Describe the general classification of lipids and fatty acids.(10 marks)
ii.Write notes on secondary metabolites. (10 marks)
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