Which Problem Is Encountered by Freshwater Systems

question 74

Multiple Choice

Which problem is encountered by freshwater systems?

• A)Eutrophication is a natural process that can occur only with the influence of humans.
• B)Acid deposition represents a more serious hazard to lakes than rivers.
• C)Rivers are more vulnerable than lakes to contamination by plant nutrients, oil, toxins, and pesticides.
• D)Eutrophication has increased with the depleting ozone layer in the last 10 years.

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Definitions:

Light-Sensitive Proteins

Proteins in photoreceptor cells that respond to light and are crucial for vision.

Retinas

The light-sensitive layer of tissue at the back of the eye that converts light rays into neural signals that are sent to the brain for visual recognition.

Melatonin

A hormone that regulates the sleep-wake cycle, produced by the pineal gland in response to darkness.

Pineal Gland

A small endocrine gland in the vertebrate brain that produces and regulates some hormones, including melatonin, which affects sleep patterns.