Nervous System

http://www.brainpop.com/health/bodysystems/nervoussystem/

Structures of the nervous system

• The nervous system is made up of the brain, spinal cord and nerves.

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

• The peripheral nervous system (PNS) consists of all nerves outside of the central nervous system.

Function of the nervous system

The nervous system functions

1. to receive information

2. respond to stimuli

3.to maintain stable internal conditions.

Receiving Information

• Your nervous system makes you aware of what is happening in the environment around you.

• It lets you know that a ball is zooming toward you, your favorite song is on the radio and that the pizza in your hand is hot.

• Your nervous system also checks conditions inside your body, like glucose levels in your blood.

Responding to Stimuli• The nervous system

responds to external stimuli like laughing at a funny movie.

• The nervous system also responds to internal stimuli such as the body’s need for more oxygen by increasing the heart rate.

Maintaining Stable Internal Conditions

• The nervous system helps the body to maintain homeostasis by directing the body to respond appropriately to the information it receives.

• For example, when you are hungry your nervous system directs you to eat.

The Three Parts of the Brain are:

•Cerebrum Interprets input from

sense organs, controls voluntary movement, and is responsible for learning and memory.

http://www.brainpop.com/health/bodysystems/brain/

Cerebellum

Coordinates your muscle movements and helps you keep your balance.

Brainstem Controls

involuntary actions such as your heartbeat, breathing and reflexes.

Cerebrum

Brainstem

Cerebellum

http://www.brainpop.com/health/bodysystems/spinalcord/

Neurons- nerve cells

• Neurons are cells that carry information through your nervous system.

• The information is carried in what is called a nerve impulse.

http://www.brainpop.com/health/bodysystems/neurons/

Three Types of Neurons

• Sensory NeuronsPick up stimuli from internal or external environment and converts it to an impulse.

Motor Neurons

• Send an impulse to a muscle, and the muscle contracts in response.

InterneuronLocated in the brain or spinal cord and carries the nerve impulse from one neuron to another.

Reflexes• A reflex is an automatic response that

occurs very rapidly and without conscious control.

• The contraction of skeletal muscles is usually controlled by the brain, but in reflexes the muscles react with the involvement of the spinal cord only – not the brain. This protects us from danger.

• http://faculty.washington.edu/chudler/chgames.html

• http://faculty.washington.edu/chudler/words.html

Sources:• http://www.georgiapainphysicians.com/l2_edu_pharma_mod1_slides.htm

• http://www.omsusa.org/pranzatelli-Brain.htm

• http://www.unitedstreaming.com