THE ENDOCRINE AND IMMUNE BODY SYSTEMS

YOUR AMAZING BODY

SYSTEMS OF THE BODY

Do you remember that the human body is made up of systems?

Here’s another fact you have learned: each system is made up of organs. The organs are made up of tissues, and the tissues are made up of cells.

REVIEW OF BODY SYSTEMS

Can you remember the six systems of the body we have already learned? Yes? . . . No? . . . Maybe so?

Perhaps some hints would help!

Here’s your first clue:

Yes, the heart is part of

The

Circulatory System!

OK; try another system--here’s your hint:

Hopefully a lunch made you think about chewing, swallowing and digesting your food . . .

…which made you think of . . .

The Digestive System!

How are you doing?

Are you two for two?

Try a third one!

Here’s the next system— and here’s your hint:

Do the cheerleader’s motions make you think about the way muscles stretch and contract to help us move?

Then I’m sure you’ve guessed . . .

The Muscular System!

Here’s a hint about the fourth body system:

In what part of the body do dreams exist?

If you said “the brain,” then you’re on the right track. The brain is part of . . .

The Nervous System!

Here’s the fifth system— ready to guess?

What body organs could help you blow air through a bubble wand?

Did you say “lungs?” If so, you’re correct. Lungs are part of . . .

The Respiratory System!

Are you ready for the next system? Here’s your hint . . .

Have you ever seen an x-ray?

This x-ray shows two bones. Bones are part of . . .

The Skeletal System!

Let’s say all six together . . .

• The Circulatory System

• The Digestive System

• The Muscular System

• The Nervous System

• The Respiratory System

• The Skeletal System

Two More Body Systems

Today you will learn about two more body systems. These systems are the immune and endocrine systems.

These systems are very complex and interesting, but we don’t usually notice them until they fail for some reason.

Hopefully, learning some facts about these systems will help you understand what is happening in your body.

Plus, you may hear news stories about new medications or treatments that come on the market, and knowing about the immune and endocrine systems will make those news stories more understandable.

The immune and endocrine systems help our bodies adapt to our environment. “Adapt” means to adjust to different places or situations.

Let’s say, for example, the classroom became very hot. You might adapt, or adjust to the environment by unbuttoning the collar of your shirt or taking your jacket off.

The Immune and Endocrine Systems

Today you will learn about the functions of the immune and endocrine systems.

Listen closely so you can learn four examples of the many ways these body systems help humans adapt to their environment.

The Immune System

You’ve heard about computer viruses, haven’t you? When a virus gets into a computer’s hard drive, it ruins the system.

Sometimes the computer can be fixed, but if the virus is a severe one, the computer may have to be replaced.

Believe it or not, computer scientists understand some of these technical problems by studying the human body!

The Immune SystemInside your body is an amazing protection mechanism called the immune system. It is designed to defend you against millions of bacteria, microbes, viruses, toxins and parasites that would love to invade your body.

To understand the power of the immune system, all you have to do is look at what happens to anything once it dies. That sounds gross, but it shows something very important about the immune system.

When something dies, its immune system shuts down. In a matter of hours, the body is invaded by all sorts of bacteria, microbes, and parasites.

Few of these things were able to get in when the immune system was working, but the moment the immune system stops, the door is wide open!

Once an animal or human dies, it only takes a while for these organisms to completely dismantle the body and carry it away, until all that’s left is a skeleton.

The good news is that your immune system is doing something amazing to keep all that dismantling from happening while you’re alive!

The Endocrine System

You may never have heard of the endocrine system. This little-known system is made up of a collection of glands. Some of these glands are small, but they do very BIG things!

The endocrine system controls, or regulates, a number of your body’s functions. How? Through chemicals.

Where do these chemicals come from? Some come from a few organs, like the stomach or kidneys, that produce them and ooze them. The chemicals your organs make are used close to that organ.

The endocrine glands throughout your body make chemicals called hormones that travel much further. Endocrine glands put hormones directly into your bloodstream. Maybe you didn’t know that all these chemicals travel to every part of your body. But they do, and they're acting as chemical messengers.

You have over 30 hormones busily controlling and regulating such things as:

•when you feel hungry or full;

•how you sleep;

•your body temperature;

•how you break down and utilize the food you eat and whether you are fat or thin;

• how you handle stress—

•even how and when you grow.

Phew—That’s a LOT!

Other chemicals are produced by your exocrine glands.

These glands make sweat and saliva, and they are part of the endocrine system, too.

Let’s take a look at these two systems in

YOUR

AMAZING

BODY!

Work of the Immune System

Your immune system is like a soldier, on guard to defend your body against invasions by germs and viruses.

For example, when you get a cut, all sorts of bacteria can enter your body through the break in the skin.

Your immune system responds and gets rid of the invaders while the skin heals itself and seals the wound.

If the immune system misses something, the cut may get infected, swollen, or filled with pus.

Swelling or pus are both side-effects of the immune system doing its job.

If too many bacteria get into your body, your immune system may respond by moving blood from your skin’s surface to the interior of your body. This response is called a fever.

Usually, a fever is your body’s way of defending you against infection.

Work of the Endocrine System

Remember, the immune and endocrine systems help your body adapt to your environment.

Imagine standing onstage saying a part in a play, being in the desert, or exercising in the gym. Nervousness, high temperature, or exertion might make you begin to perspire, or sweat.

Sweating is the body’s way of getting rid of excess body heat. Most people have over 2 million sweat glands in their skin!

As you sweat, the moisture on the surface of your skin evaporates, and you cool off.

You can be thankful for your endocrine system because if you couldn’t adapt to heat, you might have a heat stroke!

The Pituitary Gland

Another part of the endocrine system is the pituitary gland. This gland is often called the “master” gland, because it influences other endocrine glands.

Chemical messages from this gland help determine how short or tall you will be.

Today we reviewed the names of the six body systems you’ve already learned. Then you heard about two more body systems: the immune and the endocrine systems.

When all the systems of the body work together, we enjoy good health.

The Amazing Human Body

In the Bible David said, “I thank you, High God—you're breathtaking! Body and soul, I am marvelously made!”

You can thank God for creating your amazing body.

Resources

http://www.kidshealth.org/parent/general/body_basics/endocrine.html

http://health.howstuffworks.com/immune-system.htm/printable

http://yucky.discovery.com/flash/body/pg000133.html

http://wellercenter.org/images/Enrichment%20PDFs/LB.pdf

The Endocrine System

http://library.advanced.org/10348/find/content/endocrine.html