LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
B.Sc. DEGREE EXAMINATION –PLANT BIOLOGY & PLANT BIO-TECH.
SUPPLEMENTARY EXAMINATION – JUNE 2007
PB 6605 / 6602 - ENVIRONMENTAL BIOTECHNOLOGY
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. Condition of atmosphere which promotes rapid mixing of contents of the air is ….
a. neutral atmosphere
b. stable atmosphere
c. unstable atmosphere
d. atmospheric inversion
02. Secondary treatment process is used in the removal of
a. fine suspended and dissolved organic solids
b. suspended organic solids
c. floating materials
d. settleable organic solids
03. The normal size of the flocs in activated sludge are
a. 0.2 to 1 mm in diameter
b. 1mm to 5 mm in diameter
c. 0.1 to 0.5 mm in diameter
d. 0.4 to 0.8 mm in diameter
04. The bacteria which is dominant in biofilm formation is
a. Fusarium sp.
b. Zoogloea ramigera
c. Amoeba
d. Geotrichum sp.
05. Rhizofiltration is a ----------- remediation technique
a. soil
b. water
c. surface water and ground water d. soil and water
II State whether the following statements are True or False
(5 x 1 = 5 marks)
06. Highest rate of oxidation takes place in the lower region of the trickling filter bed.
07. The carbon: nitrogen ratio suitable for biogas production is 1 : 1.
08. The successful operation of the activated sludge process is dependent on the ability
of the floc to absorb substrates.
09. Biostimulation speeds up the natural remediation process.
10. Aerobic condition promotes the growth of BTEX degrading bacteria.
III. Complete the following
( 5 x 1 = 5 marks)
11. The residual, incompletely decomposed organic matter left after the microbial action
is called ____________.
12. ____________ play a major role in breakdown of substrate in to gas form.
13. Due to their unusual stability, ___________ were widely used as non- flammable –
heat resistant oils in heat transfer systems.
14. The light weight circular discs used in rotating biological contactors are made up of
_____________.
15. ____________ treatment process of water is required to remove phosphate and nitrogen.
IV. Answer all, each in about 50 words
16. Write short notes on Bacteriorhodopsin.
17. Define atmospheric inversion.
18. Distinguish between compost and composting.
19. Differentiate metaboliser from co- metaboliser
20. What is Biocorrosion?
( 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. Summarise the physico chemical characteristics of water.
22. Enumerate the characteristics of lentic aquatic system.
23. Describe the activated sludge process.
24. What is sedimentation? Briefly write about different types of settling and
sedimentation tank.
25. Briefly write about biological removal of nitrogen and phosphorus.
26. Explain different types of phytoremediation techniques.
27. Elaborate on bioremediation of DDT and Pentachlorophenol.
28. What is biomineralisation? Add a note on microbial and multicellular
biomineralisation.
PART C
( 2 x 20 = 40 marks)
Answer the following, each within 1500 words only. Draw diagrams and flowcharts wherever
necessary.
29 a. Describe the steps involved in the microbial production of ethanol by fermentation.
OR
b. Give a detailed account on microbial metal resistance mechanisms.
30 a. Write an essay on in situ and ex situ bioremediation.
OR
b. Write notes on the following
i.
Structure, development and importance of biofilm.
ii.
Bioleaching of metals
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