Homeostasis and the receptors and effectors that carry it out, and how negative feedback restores a set point while positive feedback drives further away from it.

What you need to know

Answer each one before you reveal it.

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Process

Explain homeostatic control by negative feedback.

Key term

Compare negative and positive feedback.

Process

How does negative feedback differ from positive feedback in terms of stability?

Questions from this subtopic

Each one with the model answer underneath.

1
Define homeostasis.
Model answer
The maintenance of a constant internal environment despite changes in external conditions.
2
What is a receptor in the context of homeostasis?
Model answer
A cell or structure that detects stimuli or changes in the internal or external environment.
3
Define an effector.
Model answer
A cell, tissue or organ that brings about a response to a stimulus.
4
What is the functional difference between receptors and effectors?
Model answer
Receptors detect changes in conditions, whereas effectors carry out responses to restore conditions.
5
Define negative feedback.
Model answer
A mechanism where a change from the set point triggers responses that return the system back towards the set point.
6
Define positive feedback.
Model answer
A mechanism where a change from the set point triggers responses that amplify the change further away from the set point.

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Homeostasis, negative and positive feedback

Overview