A system that controls all of the activities of the body.

The nervous system is made of:

The brain The spinal cord

The nerves The senses

The environment is everything outside the body.

The sense organs gather information from outside the

body, then send the messages to the brain.

The nervous system also allows you to react to a stimulus on order to keep the body in

homeostasis.

A stimulus is a change in the environment.

Example: A hot stove

Or… tripping over a rock

Your reactions are automatic.

Automatic means that you do not have to think about your

reactions.Example: If a bug flies by your eye,

you will blink.

* The Central Nervous System controls all of the body’s activities.

* The Central Nervous System is made of two main organs.

1. The brain

2. The spinal cord

Is divided into two hemispheres-the right and left side of the brain

The right side controls the left side of the body and left half controls the right side.

* An organ that controls your emotions, your thoughts, and every movement you make. The brain controls everything in the body.

* The brain is made of more than 10 billion nerves!

* The brain is divided into three parts and is protected by the skull.

* The Brain has three main parts…

1. The Cerebrum

2. The Cerebellum3. The Brain Stem

* The Cerebrum is the largest part of the brain.

1. The cerebrum controls your thinking.

2. The cerebrum controls your memory.

3. The cerebrum controls your speaking.

4. The cerebrum controls your movement and identifies the information gathered by your sense organs.Corpus Collosum connects the two

hemispheres

* The cerebellum is below and to the back of the cerebrum.

1. The cerebellum controls you balance.

2. The cerebellum controls your posture.

* The Brain Stem connects the brain to the spinal cord.

* The nerves in the brain stem control your heartbeat, breathing, and blood pressure. Also called the lizard brainBrainstemsong

Hippocampus and Hypothalamus

• Hippocampus converts learning to working memory

• Hypothalamus-controls hunger, thirst and temperature and emotion

* The spinal cord sends messages to the brain.• The spinal cord is the part of the nervous system that connects the brain to the rest of the nervous system.

• The spinal cord is protected by a series of bones called the vertebrae.

Review of the brain

1. What is the job of the cerebellum?2. If you are left handed, then which

hemisphere of your brain do you use most? What part of the brain is this?

3. Your heart beat is controlled by which brain part?

4. What is the difference between the hypothalamus and hippocampus?

Messages carried throughout the body by nerves.

* An automatic reaction that happens without thinking about it.

* A reflex happens quickly in less than a second.

* The Outer Nervous System’s job is to connect the Central

Nervous System to the rest of the body.

* The outer nervous system carries messages between the central

nervous system and the rest of the body.

* The outer nervous system controls the body’s activities that you don’t think about.

* The outer nervous system controls activities in your small

intestine, your breathing, and your heartbeat.

controls

• Motor Nerves

– Send electrical signals through nerves to contract muscles to create motion

You have a nerve along your whole arm.

The “funny bone” is the only place on the arm where the nerve is not

protected.

The “funny bone” is on the elbow.

* The outer nervous system is made of the nerves and the sense

organs.

Ear

EyeSkin

Nerves

Tongue

Review Nerves

• Draw a three part Venn Diagram comparing the three nerve types.

Sensory

Automatic

Motor

Vision is your ability to see.

Vision involves the eye and the brain.

Parts:

Cornea-outside covering of the eye

Iris-muscle of the eye that regulates how much light enters the eye (colored part)

Lens-part of the eye that focuses light

Vitreous humor-liquid in the eye that gives the eye its shape

Pupil-hole in the eye that light travels through

Sclera-white part of the eye

Aqueous humor-liquid sac that gives cornea its shape.

Retina-specialized cells in the back of the eye that takes light to a signal

Optic nerve-sends signal from the back of the eye to the brain.

Label the eye

Eye cont:

Rods-specialized cells that pick up color

Cones-specialized cells that pick up color

Why do we see color?• http://phet.colorado.edu/simulations/sims.php?sim=Color_

Vision

How do cones benefit us?

How do rods benefit us?

Ever seen a red eye photo? You are actually taking a picture of the back of someone’s eye

Colorblind Test

Stroop Test

Optical Illusions

• http://www.michaelbach.de/ot/

Retinal BurningStare at Dot-30 seconds

Blink

Eye Review

• How are the cells of the eye specialized so that we are able to see? Explain how the parts function so that we are able to observe the world around us.

When a sound is made, the air around the sound vibrates.

Hearing starts when some of the sound waves go into the

ear.

How do we hear?

There are nine main parts of the ear.1. Pinna

2. Ear canal3. Ear drum

5. Anvil

6. Stirrup

7. Cochlea

4. Hammer 8. Eustachian tube9. Auditory nerve

Ear

The ear canal is the tube between the outside of the ear and the ear drum.

The ear drum is in the middle ear. It vibrates when sound waves hit it.

The pinna is the part of the ear that you can see.

The three smallest bones in the body, the hammer, the anvil, and the stirrup, are in the

middle ear.The hammer gets the vibrations from the eardrum, then sends them to the

anvil.The anvil passes the vibrations to the stirrup. The stirrup

passes the vibrations

to the inner ear.

The inner ear is made of the cochlea and liquid.

The cochlea is in the inner ear. The cochlea looks like a shell. Filled with hair cells that

move and send an electrical signal.

The Eustachian tube controls the amount of pressure in the ear. “Ear

popping”

The auditory nerve carries the hearing information to the brain from the cochlea and

the brain tells us what we heard.

The ear works with the brain to control your balance.

All of your movements are controlled by balance and muscles.

The liquid in your inner ear is responsible for your balance.

The liquid in your ear moves when we move. The liquid movement sends

information to the brain to tell it how we are moving.

Ear Review

• How does our ear allow us to hear?• Why do you think that listening to loud

noises over a long period is bad for hearing?

The sense of touch is located in the skin.

The nerves in the skin allow us to feel texture, pressure,

heat, cold, and pain.

Texture is how something feels.

Touch review

• Why is such a sensitive touch so necessary for survival?

The nose controls your sense of smell.

The nose is able to smell 80 different kinds of smells.

Your sense of taste comes from the taste buds in the tongue.

Taste buds are the parts on the tongue that allow us to taste.

The four kinds of taste buds are sweet, sour, bitter, and salty.

Did you know? Your nose affects your sense of taste. Think about colds