You accidentally cut your hand. Blood platelets in the area begin to attach to the broken blood vessels in the wound. What needs to happen next to create a positive feedback mechanism?
A)The platelets change shape to encourage more to rush in and stick to each other to form plugs over the broken vessels.
B)The action of platelets sticking to the broken area signals for blood to stop flowing to that area, stopping the bleeding.
C)The sensation of pain in your hand causes your muscles to jerk your hand away from the danger.
D)The platelets send signals to the brain to slow heart rate and slow the bleeding.

Question

You accidentally cut your hand. Blood platelets in the area begin to attach to the broken blood vessels in the wound. What needs to happen next to create a positive feedback mechanism?
A)The platelets change shape to encourage more to rush in and stick to each other to form plugs over the broken vessels.
B)The action of platelets sticking to the broken area signals for blood to stop flowing to that area, stopping the bleeding.
C)The sensation of pain in your hand causes your muscles to jerk your hand away from the danger.
D)The platelets send signals to the brain to slow heart rate and slow the bleeding.

Quizplus · Accepted Answer

A positive feedback mechanism would involve the platelets stimulating more platelets to rush in and stick together to form a plug over the wound. This is facilitated by the platelets changing shape and releasing chemicals that attract more platelets. The more platelets that attach to the wound, the stronger the plug becomes, and the more effective it is at stopping bleeding. This is an example of positive feedback, as it amplifies the initial stimulus (the injury) to promote healing.

You Accidentally Cut Your Hand