The ?Rst Cells Appeared About _____ Billion Years Ago

question 51

Multiple Choice

The ?rst cells appeared about _____ billion years ago.

• A) 5
• B) 4
• C) 3.5
• D) 2
• E) 1

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Definitions:

Dopamine Antagonist

A type of drug that blocks dopamine receptors, reducing the effect of dopamine in the brain.

Antianxiety Agents

Medications or substances used to reduce or alleviate anxiety and its related disorders.

Benzodiazepines

A class of psychoactive drugs used primarily for treating anxiety, insomnia, and several other conditions, known for their tranquilizing effects.

Alcohol

Alcohol typically refers to ethanol, a psychoactive substance found in drinks like beer, wine, and spirits, affecting the central nervous system with both stimulating and depressing effects.