The Following Figure Shows Studies in a Stream Where Enclosures

question 31

Multiple Choice

The following figure shows studies in a stream where enclosures were set up either with trout or with no trout.Which statement is a correct interpretation of the graph about trout, invertebrates, and algae?

• A)If trout are present in a system, algae production is low and invertebrate population levels are also low.
• B)If trout are present in a system, algae production is high and invertebrate population levels are also high.
• C)If trout are present in a system, algae production is high and invertebrate population levels are low.
• D)Trout do not seem to affect the algae production; only the invertebrate populations are affected.

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Definitions:

Drive-Reduction Theory

A psychological concept suggesting that motivation arises from biological needs that push organisms to seek homeostasis through reducing drives stemming from those needs.

Tension

The physical or emotional strain caused by conflicting or demanding circumstances.

Stability

The condition of being resistant to change or variation, often used in psychological contexts to refer to emotional or mental consistency.

Primary Drives

Basic, instinctual drives that motivate behaviors necessary for survival, such as hunger, thirst, and avoidance of pain.