1. Find your Science Journal and copy these charts.
What is it?
What does it do?
Heart
Atriums
Ventricles
Vessels
Arties
Veins
Capillaries
Blood
Plasma
Red Blood Cells
White Blood Cells
Platelets

2. The circulatory system is made up of the heart, veins, arteries and blood.
Despite some misconceptions, the heart is not one big, open organ through which blood runs. Instead, it is about the size of your fist and is broken into four separate chambers (rooms).
Why does it make sense that a shorter, smaller person can be healthy with a smaller heart?

3. There are two upper and two lower chambers
There are two upper and two lower chambers. The upper chambers are called the atriums (left and right) and only receive blood from the body.
The lower chambers are called the ventricles(left and right), and their task is to send blood out to the body.

4. Three main types of blood vessels carry blood throughout our bodies:
How does blood travel through your body? Are you like a big water balloon filled with blood?
Three main types of blood vessels carry blood throughout our bodies:
The arteries carry oxygenated blood (blood that has received oxygen from the lungs) from the heart to the rest of the body.
The blood then travels through the veins back to the heart and lungs, where it receives more oxygen.
Capillaries connect arteries and veins.

5. As the heart beats, you can feel blood traveling through the body at your pulse points — like the neck and the wrist — where large, blood-filled arteries run close to the surface of the skin.

6. FAQ – Is blood always red?
Blood is red, inside your body and out. That is, unless you’re a fictitious character such a Vulcan from Star Trek, then your blood may be green or some other color. But if you’re a human being from the planet Earth, your blood is red!

7. FAQ – Why does the blood that I can see in the veins in my wrist look blue?
The reason your veins appear blue is because you are looking through your skin. A phlebotomist wrote of an experiment using glass tubes of blood immersed in milk, in which they appeared blue at a certain depth for the same reason.

8. What is blood made of?
Blood is made up of many different things: plasma (5%) and water (50%), white blood cells and platelets (<1%), and red blood cells (45%).

9. The plasma is a water and salt substance that contains the blood's proteins. It allows blood to flow.
The white blood cells are known as the army and fight off infections and diseases.
Platelets are the smallest cells in the blood. They form clots to stop the flow of blood in case you have an injury.
Red blood cells contain hemoglobin, which is responsible for carrying oxygen to your body. Blood has many important jobs!

10. Unfortunately, sometimes the heart, veins, or arteries can become blocked by cholesterol, which does not allow the blood to flow through your body. Your body needs oxygen to survive, so imagine what would happen if you could not get blood moving through your body to obtain this essential oxygen. To prevent heart attacks, medical engineers have worked to create devices to clear such blockages.

11. One common procedure used to clear clogged arteries is called angioplasty. During this procedure, a tiny balloon is inserted into the clogged artery and is then inflated. The artery opens, and then the doctor places a device called a stent into the artery to keep it open after the procedure is completed. This allows the blood to flow through the area of the artery that was previously blocked.

12. The Circulatory System
* Complete “Blood Cell Model” & “Blood Cell Math”
* Read pgs 56 – 61 in the student book * Sketch a diagram of your heart in your journal
* Why is it important for a blood cell’s membrane to be flexible enough for the cell to change shape?

13. Why is the heart important?
What can doctors do if your heart doesn’t work the way it should?

14. Sketch this chart in your science journal.
Resting Heart Rate
Immediately After Exercise
3 Minutes After Exercise

15. The Circulatory System
3 Volunteers Needed

16. Immediately After Exercise 3 Minutes After Exercise
What prediction can you make about heart rate before, during, and after 1 minute of rigorous exercise?
Resting Heart Rate
Immediately After Exercise
3 Minutes After Exercise

17. Answer in your journal:
Why is it important for your heart to beat faster when you exercise?