Circadian Rhythms Are

question 7

Multiple Choice

Circadian rhythms are

• A) endogenous cycles of activity over the course of a day.
• B) not found in plants.
• C) learned patterns of daily activity.
• D) annual changes in behavior (such as migration).
• E) monthly cycles of reproductive activity.

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Definitions:

Shingles

A viral infection caused by the varicella-zoster virus, leading to a painful rash, usually on one side of the body or face.

Cornea

A transparent area on the front of the outer layer of the eye that acts as a window to let light into the eye.

Pupil

The opening at the center of the iris, which grows smaller or larger as the iris contracts or relaxes, respectively; it regulates the amount of light that enters the eye.

Lens

A clear, circular disc located in the eye, just posterior to the iris, that can change shape to help the eye focus images of objects that are near or far away.