Transcript The Nervous System

The Nervous System
Function of the Nervous System
1. Receives information about what is
happening both inside and outside
your body.
2. Directs the way in which your body
responds to this information.
3. In addition, your nervous system
helps maintain homeostasis.
Structure of the Nervous System
• Nervous system can be broken down into
two parts, the Central and the Peripheral
nervous system.
Central Nervous System
1. Brain- controls all the functions of your body.
-made of interneurons
Cerebrum- interprets input from the senses,
controls movement and carries out complex
mental processes (example: learning and
remembering).
Cerebellum- coordinates the actions of your
muscle (balance).
Central Nervous System con’t
4. Brain Stem- controls your
body’s involuntary actions
(heart beat).
5. Spinal Cord- link between your
brain and the peripheral nervous
system.
Peripheral Nervous System
Network of nerves that branch out from the
central nervous system and connect the rest
of the body.
Structure of a Nerve Cell
• Neuron- the cell that carries the information
through your body.
Structure of a Nerve Cell
• A neuron has a large cell body that contains
the nucleus.
• Dendrites - threadlike extensions on the cell
body that carry impulses toward the neuron’s
cell body.
• Axon - carries impulses away from the cell
body.
dendrites
cell body
nucleus
axon
Types of Neurons
1. Sensory Neurons- pick up stimuli from the
internal or external environment and convert
into a nerve impulse.
2. Interneurons- are neurons that carry impulses
from one neuron to another.
3. Motor Neurons- sends an impulse to a muscle
or gland to react in response.
How an Impulse is Transferred:
• - The junction where one neuron meets
another and an impulse is transferred is called
a synapse. For a nerve impulse to be carried
along at a synapse, it must cross the gap
between the axon and the next structure. The
axon tips release chemicals that carry the
impulse across the gap.
Brains