In Which State Is Most of a Person's Sleep Time

question 115

Multiple Choice

In which state is most of a person's sleep time spent?

• A)dreaming.
• B)in REM sleep.
• C)in paradoxical sleep.
• D)in NREM sleep.

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Definitions:

Extracellular Matrix

A complex network of proteins and carbohydrates outside cells, providing structural and biochemical support to surrounding cells.

Collagen

A primary structural protein found in skin and connective tissue, responsible for skin elasticity and strength.

Derived Characteristic

A trait that is present in an organism but was absent in the last common ancestor of the group to which the organism belongs.

Sessile Animals

Organisms that do not move about and are fixed in one place, such as corals and barnacles; they are often anchored to a solid surface.