1. What is the function of the heart? 

The human heart is an organ that pumps blood throughout the body.

2. How many chambers make up the heart?

The human heart has four chambers: two upper chambers (the atria) and two lower ones (the ventricles).

3. What is the difference between veins and arteries? 

Arteries takes the blood away from the heart to the body.

Veins takes the blood to the heart

4. How does blood circulate through each chamber of the heart? 

Blood enters the right atrium and passes through the right ventricle. The right ventricle pumps the blood to the lungs where it becomes oxygenated. The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium. From the left atrium blood flow into the left ventricle.

5. How does blood flow to and from the lungs? 

Once blood travels through the pulmonary valve, it enters your lungs, oxygen travels from the tiny air sacs in the lungs, through the walls of the capillaries, into the blood. At the same time, carbon dioxide, a waste product of metabolism, passes from the blood into the air sacs

6. How does blood flow to and from the tissues of the body? 

blood moves through the circulatory system by pumping out by the heart. Blood leaving the heart through the arteries is full of oxygen. The arteries branch off into smaller and smaller tubes. These bring oxygen and other nutrients to the cells of the body's tissue and organs.

7. What is the significance of oxygen and carbon dioxide? 

The blood travels from larger and smaller arteries and into the capillary network. There the blood drops off oxygen, nutrients and other important substances and picks up carbon dioxide and waste products.When we breathe out, carbon dioxide leaves our body