You Acquire a Soil Sample and Run an Enrichment Culture

question 19

Multiple Choice

You acquire a soil sample and run an enrichment culture on it. You provide the organisms in the culture with all of the ingredients required for growth except for nitrogen. What result do you expect to have at the end of your experiment?

• A) Nitrogen-fixing bacteria will significantly outnumber those incapable of fixing nitrogen.
• B) Nitrogen-fixing bacteria will not be present in the culture.
• C) Nitrogen-fixing bacteria will be present but not at significantly greater numbers than non-nitrogen-fixing species.
• D) Nitrogen-fixing bacteria will be present, but will be significantly outnumbered by non-nitrogen-fixing species.

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Definitions:

Antibodies

Proteins made by the immune system to identify and neutralize foreign objects like bacteria and viruses.

Insulin

An insulin-producing pancreatic hormone that manages glucose levels in the blood by assisting its absorption into bodily tissues.

Calories

A unit of energy used to quantify the amount of energy provided by foods and beverages.

Atherosclerosis

The buildup of fatty deposits (plaque) on the lining of arteries.