1. Homeostasis and Feedback Mechanisms

2. Living Things Maintain a Stable Internal Environment
Homeostasis: The ability to maintain stable conditions that are necessary for life.
Animals: Sweating, shivering, thirst, hunger.
Plants: Plants grow towards the light and away from gravity.

3. Feedback Mechanisms
Homeostasis is maintained by internal feedback mechanisms.
Feedback mechanisms return the body to its normal set point.

5. Feedback Mechanisms
Negative feedback – puts the body back into its original state by inhibiting the stimulus that’s causing the change.
Temperature
Blood pH
Blood sugar
Calcium levels
Blood pressure
Most feedback mechanisms in the body are negative feedback

6. Feedback Mechanisms
Positive feedback – Increases the stimulus causing more of the effect.
Childbirth – oxytocin
Blood clotting
Lactation