Download Nervous System study guide

NERVOUS SYSTEM STUDY GUIDE
The three main parts are: the brain, spinal cord (medulla) and nerves (neurons).
The brain (master control center) has three main parts:
1. Cerebrum: largest area. Controls thinking, memory, senses, and feelings
2. Cerebellum: under the back part of the cerebrum. Controls balance and movement.
3. Brain stem: the smallest part of the brain where the medulla is located. Controls body
temperature, breathing and digestion.
The brain weighs about 3 pounds and is protected by our skull.
Nerve cells carry messages to and from the spinal cord and brain, and then back to the rest of
your body. The three parts of a nerve, or neuron, are:
1. Axon: attached to the nerve cell that sends messages AWAY from cell body.
(Axon=Away)
2. Dendrite: “finger-like” projections the receive messages.
3. Synapse: the space between 2 neurons where impulses jump from one nerve cell to
another. (Synapse=Space)
Sensory nerves: Carry information to your brain from your 5 senses. (From body to brain)
Motor nerves: Bring messages from your brain or spinal cord to your organs and muscles.
(From brain to body)
Reflex- an action in response to a stimulus where a message gets sent to the spinal cord from
the sensory nerves and right back to motor nerve. (For example, when you touch something
hot and immediately move away from it)
WAYS TO PROTECT THE NERVOUS SYSTEM:
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Wear a helmet
Don’t take drugs
Wear a seatbelt in the car
Don’t dive into shallow water.