When you scratch a mosquito bite, you damage some cells. Damaged cells release histamine, which causes localized swelling that can crush additional cells, causing the release of more histamine. This is an example of

Question

Quizplus · Accepted Answer

This is an example of positive feedback because the initial reaction (release of histamine due to cell damage) leads to an amplification of that reaction (more cell damage and more histamine release), rather than reversing the initial change, which would be characteristic of negative feedback.

When You Scratch a Mosquito Bite, You Damage Some Cells