AP Biology / Unit 4: Cell Communication and Cell Cycle
4.4 Feedback
Notes
- Negative feedback reverses a change to keep homeostasis (blood glucose, body temperature).
- Positive feedback amplifies a change (childbirth contractions, fruit ripening).
Practice
Blood sugar rises; insulin lowers it. This is:
It returns to a set point.
Oxytocin increasing contractions, which release more oxytocin, is:
The change gets bigger.
Negative feedback helps maintain:
Stable conditions.
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