Suppose You Are Studying Two Small Lakes (Lake 1 and Lake

question 8

Multiple Choice

Suppose you are studying two small lakes (lake 1 and lake 2) and how they change over time. A nearby farm accidentally spills fertilizer into lake 1. Around the same time, a non-native fish-eating turtle is introduced into lake 2. The ecosystems of both lakes are affected by these changes. What processes most likely explain how the lakes were affected?

• A) Bottom-up control in lake 1; top-down control in lake 2
• B) Top-down control in lake 1; bottom-up control in lake 2
• C) Top-down control in both lakes
• D) Bottom-up control in both lakes

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Definitions:

Ghrelin

A hormone produced mainly by the stomach that stimulates appetite, increases food intake, and promotes fat storage.

Metabolic Rate

The rate at which the body expends energy or burns calories, crucial for maintaining bodily functions and health.

Basal Metabolic Rate

The amount of energy the body uses at rest to keep vital functions such as breathing and regulating body heat operational.

Set Point

A theory suggesting that each person's body weight is maintained around a biologically determined set point, leading to a stable body weight over time.