Microbiology Answers

The dense, round structures in the micrograph above are cells of one hazardous phytoplankton species present in 250ml of water sample.

   (a) How many of these cells are present in this sample?

    (b) What is the number of cells of this phytoplankton per litre of water?

(c) For this phytoplankton, 100 cells/Litre is a “trigger” value for indicating whether the water is hazardous. Does this sample exceed this “trigger” value?

With the aid of a chart outline the life cycle of plasmodium parasite

Mycotickeretis, diagnosis, history, control and treatment

Write extensively on Mycotic keratitis under the following headings:

i. History

ii. Diagnosis

iii. Treatment

iv. Control

Write extensively on Mycotickeretis under the following headings:

i. History

ii. Diagnosis

iii. Treatment

iv. Control

What are the differences between RNA and DNA viruses?

How the interferons are produced following a viral infection in a susceptible cell?

Difference between Persistence infection and Acute infection.

Which promoter initiates which life cycle (lysogenic & Lytic)? Mention both types of promoters and their characteristics.

CI has more binding capacity to the DNA than CRO- Justify the statement.

Briefly explain how microbes degrade or metabolise persistent pesticides.

Are the same thing metabolic syndrome and diabetes?

Write on the following.

1. Extra terrestrial system.

2. Quorum sensing.

1. List the 4 parameters involved in steam sterilization. (2 marks).
2. What is the difference between “saturated steam” and “super-heated steam”? (3 marks)
3. How is “dry air” removed from the autoclave in the beginning of the cycle? (2 marks)
4. State the functions of the following parts of the autoclave: (6 marks) Safety Valve 1: Safety Valve 2 : Vacuum Release Valve:
5. State 4 precautions that need to be taken when autoclaving “liquid media” in a bottle? (4 marks)
6. What is the purpose of using an ”autoclave tape”? (2 marks)
7. How much water should be added to the autoclave before you start the sterilization process? (1 mark)