1. Homeostasis Feedback Loops

2. Contractions during childbirth
When a contraction occurs, the hormone oxytocin is released into the body, which stimulates further contractions. This results in contractions increasing in amplitude and frequency.

3. Blood Clotting
The loop is initiated when injured tissue releases signal chemicals that activate platelets in the blood. An activated platelet releases chemicals to activate more platelets, causing a rapid cascade and the formation of a blood clot.

4. Breast feeding
During lactation the more the baby suckles, the more milk is produced, via a surge in prolactin secretion.