Simple Diffusion

question 18

Multiple Choice

Simple diffusion

• A) requires energy.
• B) utilizes proteins to move molecules across a membrane.
• C) moves molecules against a concentration gradient.
• D) cannot occur without a membrane present.
• E) does not require energy.

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Definitions:

Accessory Pigments

Pigments in photosynthetic organisms that absorb light energy and pass it to chlorophyll for photosynthesis, extending the range of light wavelengths that can be used.

Xanthophylls

A class of oxygen-containing carotenoid pigments responsible for many of the yellow, orange, and red hues in plants.

Alginic Acid

A polysaccharide distributed widely in the cell walls of brown algae, used as a food thickener and pharmaceutical ingredient.

Brown Algae

A large group of mostly marine, multicellular algae, including many seaweeds commonly found in colder waters.