Reflex arc

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REFLEX ARC

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Lesson objectives
To investigate the reflex arc.

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What is a reflex?
A reflex is a sudden, involuntary
contraction of muscles in response to a
stimulus.
It is a some kind of automatic response
for protection.

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Reflex arc
Reflex arc is neural pathway of nerve signals, which
include:
1. Receptor. It receives signals from outside
2. Sensory neuron. It transmits signal from receptor to
CNS, mainly to spinal cord
3. Spinal cord interneurons. They interpret the
information and decides what to do. Then it sends
signal to motor neuron.
4. Motor neuron. It carry signal from spinal cord to
effector.
5. Effector. It is an organ that produce an reflex action.

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Let’s do a labwork on p.95

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Homework
Read p. 94-95
Answer to literacy questions on p 95.
Fill in the labwork sheet.
New words