Each Year, 21

question 32

Multiple Choice

Each year, 21.7 million Americans move from one residence to another within the same county. This type of migration is known as

• A)immigration.
• B)emigration.
• C)internal migration.
• D)international.

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Definitions:

Plasticity

The brain's ability to change and adapt as a result of experience, including both structural and functional modifications.

Neural Pathways

Networks of neurons that transmit signals between different parts of the brain or from the brain to the rest of the body.

Refractory Periods

The time period immediately following an action potential during which a neuron is unable to fire another impulse.

Phrenology

A now-discredited theory which postulated that bumps on the skull could predict mental traits and character.