The Nervous SystemG5.4S.C1.PO3 - “I can identify the functions of

the nervous system."

By Dajon DeRyke, DWE

Essential Questions

• What is the Central Nervous System?• What transports messages?• What acts as the relay mechanism?• What acts as the control center?

What the Central Nervous System Does:

• Controls body movement and the five senses

• Helps control body functions such as breathing and digesting

• Enables a person to think, talk, feel pain and pleasure, learn, and remember

Central vs.Peripheral

• The central nervous system consists of the brain and spinal cord.

• The peripheral nervous system consists of all of the nerves that branch out from the spinal cord and the brain to the rest of the body.

Central Nervous System

• Consists of the brain and spinal cord

• Receives messages from and sends orders back to the body’s muscles, glands, and organs.

The Brain

• Has 3 main parts: the cerebrum, cerebellum, and the medulla

• Is soft and jelly-like, weighing two to three pounds.

• Controls movement, speech, hearing, sight, taste, smell, touch.

The Cerebrum

• Controls higher-level thinking activities.

• Problem solving and critical thinking skills

The Cerebellum

• Controls muscle coordination• Touch your nose, look up! These things are

controlled by your cerebellum

The Medulla• Controls vital, involuntary body processes• Breathing, your heart beat, and reflexes

The Spinal Cord

•A long string of nerve tissue that extends from the brain and runs through the inside of the back bone. •Acts as a two-way tunnel connecting the brain with the peripheral nervous system.

The Peripheral Nervous System

• Includes the nerves that branch out from the spinal cord and the base of the brain to the rest of the body

• Sends sensory messages to and from the brain

• Tells your body when to move

Nerves

• Form the pathway that carries electrical messages to and from the brain

• Like wire cables that can be as thin as a thread or as thick as a pencil

• They carry “messages” to and from all parts of your body to all parts of your body.

Acting Together

• The Central Nervous System, Peripheral Nervous System, and the nerves all act together to enable you to do EVERYTHING that you do!

• Pretty amazing, huh?

Nerve Cells

Nerve cells or neurons carry messages from all parts of your body to your spinal cord and brain. They carry messages away from your spinal cord and brain to all parts of your body.Messages to and from your brain travel

through the spinal cord.Your brain is the control center of your

body.

Neurons (Nerve Cells)

Neurons are made up of a cell body, a nucleus, an axon and dendrites.Dendrites are short strands that bring

messages to the cell body.The axon is a single, long strand that comes

out of the other side of the cell body and carries messages away from the cell body.

Neurons (Nerve Cells)

The message that travels through the neuron is called an impulse. Even though impulses move from neuron

to neuron, they do not touch one another. Between two neurons, there is a gap called a synapse. This is the space between neurons where electrical and chemical signals jump from neuron to neuron.

Closure

• Look through your notes for the three parts of the brain.

• Tell your face partner which part of your brain controls muscle coordination!

• What does the spinal cord do?• Tell your shoulder partner!