In the 1930s, the Navajo Nation Treated Sheep and Cattle

question 62

Multiple Choice

In the 1930s, the Navajo Nation treated sheep and cattle for ticks and other parasites by using concrete "dip tanks," a common practice in the United States during that time period. Animals were herded into one end of the tank and out the other. Each day, the tanks were filled with 200,000 gallons of insecticide, and any remaining chemicals were emptied onto the ground. The pesticide solution seeped into the ground, ditches, and pits around the tanks.
In the 1990s, the EPA Emergency Response Team (ERT) was called to the Navajo Nation to investigate the problem. They concluded that bioremediation procedures were the best option for cleaning up the site. Certain types of bacteria are able to feed on and digest toxic organic substances, such as pesticides, and use them as fuel for cell respiration. The ERT distributed these pesticide-eating microorganisms throughout the contaminated soil to remove the chemical residues. Once the contaminants are degraded, these microorganism populations will die off because they will have used up all of their food supply.
-What evolutionary adaptations might the pesticide-eating bacteria have that allow them to be useful in this context? They likely

• A) fed on pesticides present on the early planet Earth.
• B) fed on the tissues and blood of cattle and sheep.
• C) fed on biofilms that colonize anaerobic environments.
• D) fed on molecules with a chemical structure similar to pesticides.

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Definitions:

Psychosexual Stage

A concept in Freudian psychoanalysis that refers to the different stages of a child’s development, each characterized by a focus on pleasure from a specific body area.

Adolescents

Young people in the transitional stage of physical and psychological development that generally occurs during the period from puberty to legal adulthood.

Defense Mechanism

Psychological strategies unconsciously used to protect oneself from anxiety arising from unacceptable thoughts or feelings.

Displacement

In psychology, it's a defense mechanism where an individual shifts negative emotions or impulses from the original source to a less threatening person or object.