Page 43 - Science Course 2 (Book 1)

Mo2-L2b: What Can Help Maintain Homeostasis?

Key Concept 1. Platelets rush to the tear and form a plug that
What Can Help Maintain Homeostasis? stops the bleeding.

How does the body coordinate movement and 2. A web of fibrin forms around the platelets and
respond to stimuli? holds them in place.

3. The fibrin web catches more platelets and red
blood cells, and these form a blood clot.

Key Concept
What Can Help Maintain Homeostasis?

How do feedback systems help maintain
homeostasis?

Feedback Mechanisms
Organ systems use feedback mechanisms to
maintain homeostasis. Action

Negative feedback is a
control system that
helps the body maintain
homeostasis by sending Modifier Reaction
a signal to stop a response.

Sensor
SUMMARY
Positive feedback is a What Can Help Maintain Homeostasis?
control system that
sends a signal to Integrator Effector The nervous system coordinates the body’s
increase a response. response to external stimuli.

The body uses positive feedback to clot blood.

1. 3. When you are bleeding, the circulatory
2. system maintains homeostasis by
controlling blood loss.

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