Refer to Figure 13

question 15

Multiple Choice

Refer to figure 13.26, In the text why did the experimenters need to include a "yolk control" in this experiment?

• A) to control for exercise causing weight loss
• B) to control for food intake causing weight loss
• C) to control for aversion to water causing weight loss
• D) to control for the age of the mouse causing weight loss

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Definitions:

Tryptophan

An essential amino acid that serves as a precursor for serotonin, a neurotransmitter important in regulating mood and sleep.

Serotonin

A neurotransmitter involved in many functions, including mood regulation, digestion, and sleep, often termed the "feel-good" chemical.

Rate-Limiting Factor

A term describing the component of a process that determines the overall rate or speed of the process, often the slowest step in a series of steps.

Dopamine Synthesis

The biochemical process by which the brain produces the neurotransmitter dopamine, a crucial substance involved in movement, motivation, and the experience of pleasure.