4.5: Feedback

Question 1

What is positive feedback? Identify two examples of positive feedback loops.

Answer 1

Amplify responses, or processes, and disrupts homeostasis. Giving birth, ripening fruit (ethylene makes nearby apples ripen).

Question 2

What is negative feedback? Identify two examples of negative feedback loops.

Answer 2

Negative feedback returns the process back to its target set point. pH of blood, or temperature of the body.

Question 3

Using internal change, describe how an organism responds using feedback loops.

Answer 3

The pH of the blood changes, so the organism uses negative feedback to return to its normal level.

Question 4

Using external change, describe how an organism responds using feedback loops.

Answer 4

The environment becomes too hot, so the organism is able to use negative feedback to return its body back to a normal temperature.