A Red Crab Very Deep in Water, Where Sunlight Is

question 51

Multiple Choice

A red crab very deep in water, where sunlight is dim, appears

• A)red.
• B)orange.
• C)cyan.
• D)brown.
• E)no color-black.

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Definitions:

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Chemical messengers in the nervous system that increase the likelihood that a neuron will fire an action potential.

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A hormone produced by the pineal gland in the brain, responsible for regulating sleep and wake cycles.

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A progressive neurological disorder marked by tremors, muscle rigidity, and slow, imprecise movement, mainly affecting older people.

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A type of cancer that begins in the lungs, frequently associated with smoking and exposure to harmful substances like asbestos.