A Salmonella species is grown for 8 hours. In this time, each cell divides about four times. What is the generation time?

Match the people in column A to their contribution toward the advancement of microbiology, in column B.

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Recombinant DNA is

a. DNA in bacteria.

b. the study of how genes work.

c. the DNA resulting when genes of two different organisms are mixed.

d. the use of bacteria in the production of foods.

e. the production of proteins by genes.

Which of the following is a beneficial activity of microorganisms?

a. Some microorganisms are used as food for humans.

b. Some microorganisms use carbon dioxide.

c. Some microorganisms provide nitrogen for plant growth.

d. Some microorganisms are used in sewage treatment processes.

e. all of the above

It has been said that bacteria are essential for the existence of life on Earth. Which of the following is the essential function performed by bacteria?

a. control insect populations

b. directly provide food for humans

c. decompose organic material and recycle elements

d. cause disease

e. produce human hormones such as insulin

If a bacterium that normally lives in the gastrointestinal tract is plunged into a salty solution, what would occur?

a. halophilic adjustment

b. osmotic concentration

c. lysis

d. plasmolysis

e. nothing

After performing the streak plate method, what feature(s) would you look for on the agar plate to determine if you have a pure culture?

Match the following people to their scientific/medical contribution:

Note: Choices may be used more than once or not at all.

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A scientist who studies the role of microorganisms in the environment is a(n) __________ .

a. genetic technologist

b. earth microbiologist

c. epidemiologist

d. environmental microbiologist