Circulation Part 1 What the Heart Does

The heart pumps oxygenated blood through the body. The heart also pumps blood filled with carbon dioxide away from the body.

Oxygen is the gas we inhale. It gives life to all the cells of the body. Carbon dioxide is the gas we exhale. It is the waste product of breathing.

orysys_rev1.shtml Web Sites to Visit Scroll to components of the circulatory/cardiovascular system and click on arrow.

Circulation Part 2 Inside the Heart

The heart is a muscle. It is called cardiac muscle.

The heart muscle contracts and relaxes. When it relaxes, the heart fills with blood. When it contracts, blood leaves the heart.

The inside of the heart is hollow. The heart has four main sections. The sections are called chambers.

The top chambers are called atrium. The bottom chambers are called ventricles.

The atria are holding areas. The ventricles are pumping areas.

You can see the muscle that surrounds the ventricles. The muscles between the two sides of the heart is called the septum.

Blood flows from the atrium to the ventricles.

Circulation Part 3 Blood Vessels

Blood vessels are tubes that hold blood. There are 3 kinds of blood vessels.

Arteries usually hold oxygenated blood. Veins usually hold blood with carbon dioxide.

Capillaries can hold oxygen or CO 2. They connect arteries and veins.

Blood should always be inside of a blood vessel. Bleeding is a sign that blood is not being contained. Bleeding can occur inside or outside of the body. Bleeding should always be stopped.

Arteries always carry blood away from the heart.

ulatorysys_rev3.shtml Web Sites to Visit Please go to page 2 and view the diagram of the heart. Click views 1, 2, and 3.

Circulation Part 4 Blood

The Components of Blood Plasma is the liquid part of blood. Plasma is yellow. It is mainly water with some salt, sugar, and fat.

Red blood cells carry oxygen to all the cells. White blood cells fight infection. Platelets stop bleeding.

Circulation Part 5 Aorta and Vena Cava

The right side of the heart holds blood with carbon dioxide. The left side of the heart holds blood with oxygen.

The aorta is a large artery. It is located on the left side of the heart. It carries oxygenated blood from the left side of the heart to all the cells of the body.

Here is what the entire aorta looks like. Usually you can’t see it because it is “hiding” behind the heart.

The vena cava is a large vein. It is located on the right side of the heart. It carries blood filled with carbon dioxide from the right side of the heart to the lungs so it can be exhaled.

_circulatorysys_rev1.shtml Web Sites to Visit Please go to page 3 and view the animation blood vessels.

Circulation Part 6 Pulmonary Artery and Pulmonary Veins

The pulmonary artery brings blood filled with carbon dioxide from the heart to the lungs to be exhaled. The pulmonary artery is the only artery that carries blood with carbon dioxide.

The pulmonary veins bring blood filled with oxygen from the lungs to the heart The pulmonary veins are the only veins that carries blood with oxygen.

Web Sites to Visit Please view systemic and pulmonary circulation. There is a short quiz at the end of these animations.

The End