Circulatory System

The circulatory system moves blood from the heart through the body and back to the heart again.

Blood is the liquid that circulates around your body. It carries oxygen and food to body cells, and takes waste away.

The bright red, oxygen rich blood is pumped through the left side of the heart. The purple, oxygen poor blood returns to the right side of the heart.

The heart is the muscle behind the circulatory system.

Your heart is the size of your fist. It is inside the middle of your chest just to the left.

Your heart is a powerful pump. It tightens and relaxes about 70 times a minute to force blood through your body.

The heart has 2 sides. The right side pumps blood only to the lungs.

The left side of the heart pumps blood to the rest of the body.

The heart pumps blood to the arteries and on to the tiny capillaries.

Arteries are shaped like tubes and carry blood away from the heart.

Capillaries are the smallest of all your blood vessels. They can only be seen under a microscope.

There are over 10 billion capillaries in your body.

The arteries and capillaries bring water, oxygen and nutrients to your cells.

The veins bring the blood back to the heart. They bring with them toxic waste called: CO 2 or Carbon Dioxide.

Carbon dioxide makes us sick!

But trees l ve it!

Trees use the CO 2 or Carbon Dioxide to make food for the plant.

And in return the plants give us oxygen to breathe.

The oxygen we breathe fills our lungs with fresh clean oxygen rich air.

Now the purple, oxygen poor blood rushes to the lungs to get fresh oxygen before it makes its trip around the body once again.

Every 90 seconds the cycle repeats itself. The blood takes oxygen to the cells and returns with the poison carbon dioxide.