1. Introduction to Microbiology

Label the general phases in the carbon cycle.

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Which of the following is a beneficial activity of microorganisms?

Which of the following is an example of bioremediation?

Which of the following is true of the normal human microbiota?

Briefly state the role microorganisms play in each of the following:

a. Biological control of pests

b. Recycling of elements

c. Normal microbiota

d. Sewage treatment

e. Human insulin production

f. Vaccine production

g. Biofilms

It is possible to purchase the following microorganisms in a retail store. Provide a reason for buying each.

a. Bacillus thuringiensis

b. Saccharomyces

These organisms are important in sewage treatment and can produce a fuel used for home heating and for generating electricity.

Which of the following is an example of bioremediation?

a. Application of oil-degrading bacteria to an oil spill

b. Application of bacteria to a crop to prevent frost damage

c. Fixation of gaseous nitrogen into usable nitrogen

d. Production by bacteria of a human protein such as interferon

e. All of the above

Bioremediation refers to the use of living organisms to remove pollutants. Describe three examples of bioremediation.

Coliforms are used as indicator organisms of sewage pollution because

a. They are pathogens.

b. They ferment lactose.

c. They are abundant in human intestines.

d. They grow within 48 hours.

e. All of the above.

What is industrial microbiology? Why is it important?

Identify where the following processes occur: ammonification, decomposition, denitrification, nitrification, nitrogen fixation. Name at least one organism responsible for each process.

Potable water is allowed to have ________coliforms per 100 ml of water tested.

Nitrification converts:

a. organic nitrogen to NH3

b. NH₃ to NH₄⁺

c. NH₄+ or NH₃ to NO₃

d. NO₃ to N₂