Ergs Are ______

question 14

Multiple Choice

Ergs are ______.

• A) usually composed of silt
• B) notable for the absence of dunes
• C) sometimes originated by non- desert conditions
• D) absent from the Sahara
• E) large, crescent- shaped dunes

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Definitions:

Opponent Process Theories

A group of theories, often applied to color vision and emotional responses, suggesting that elements are paired in a system where the activation of one element inhibits the activity of the opposite element.

Trichromatic Theory

A theory of color vision proposing that the human eye perceives color through the relative rates of response by three types of cones, each sensitive to different wavelengths of light.

Afterimage

A visual image or illusion that continues to appear in one's vision after the exposure to the original image has ceased.

Opponent Process Theory

A psychological and neurological model that explains how the perception of colors is the result of opposing responses between two sets of color receptors in the eyes.