Researchers Have Found That ________ Cause(s) Increases in Dopamine Levels

question 6

Multiple Choice

Researchers have found that ________ cause(s) increases in dopamine levels in the brain.

• A) only opiates and stimulants
• B) only depressants and hallucinogens
• C) every addictive drug
• D) only alcohol and opiates

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Definitions:

Common Ancestor

The most recent individual from which all organisms in a group are directly descended.

Directional Selection

A form of natural selection where one extreme phenotype is favored over others, causing the allele frequency to shift in one direction.

Extreme Phenotype

The manifestation of traits at the extreme endpoints of a genetic expression spectrum.

Inbreeding

The breeding of closely related individuals, which increases the risk of offspring inheriting genetic defects.