Module: Cardiovascular

A Circulatory System Relay

Grade Level: 5 - 8


The heart is the main pump that forces the blood through the blood vessels of the body. There are four cavities or open spaces inside the heart that fill with blood. The two upper cavities are the atria and the two lower cavities are the ventricles. The blood coming from the lungs travels to the heart and to all the cells in the body. Once having removed the cells' carbon dioxide and wastes the blood returns to the heart and lungs to pick up a fresh supply of oxygen.

The left ventricle pumps blood that has received oxygen (in the lungs) to the brain and all the organs and extremities of the body. Weakening of the left ventricle is a serious cardiovascular problem that affects many thousands of patients. Heart transplants are the solution for some, but many will die before a transplant is available. Combining NASA's research interest in cardiovascular physiology with NASA's expertise in fluid dynamics, mechanical and electrical engineering has helped to address this problem. Partnerships between NASA and cardiovascular specialists have led to significant advancements in left ventricular assist devices. These devices are most simply described as auxiliary pumps that take a portion of the "pumping" burden from the left ventricle. These devices can pump up to 5 liters of blood per minute, with minimal damage to the blood cells and no clotting of the blood. Such devices may one day save many lives.

Key Question

Time Frame:

1 class period

Materials For each team of 5 students:

For the class:

Getting Ready Set up the relay course ahead of time in a gymnasium or on the playground (see the diagram on next page). If a gymnasium or hallway is used, mark off the parts of the circulatory system with squares of
masking tape. If the playground is used, mark off the squares with playground chalk.

Circulatory System Relay Simulation

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1. Students begin in the Left Ventricle as an oxygenated blood cell.
2. They travel through the Aorta.
3. After passing through the aorta students carry their oxygenated blood to the muscles.
4. From the muscles students carry carbon dioxide loaded blood to the Right Atrium.
5. From the Right Atrium students travel into the Right Ventricle.
6. Students travel through the Pulmonary Artery.
7. From the Pulmonary Artery students travel into the lungs where they exchange their carbon dioxide for oxygen.
8. Now carrying oxygenated blood students enter the Left Atrium and are ready to begin the circulatory cycle again.

Classroom Activity 1. Let us  review the parts of the circulatory system.
2. Study the relay course and review the circulatory pathway.
3. Work in  teams. Red balloons will represent oxygenated blood cells. Meanwhile, the blue balloons will represent carbon dioxide loaded blood cells that have given away their oxygen and are now carrying away the cells' waste.
4. Let us walk the pathway: preliminary practice

a. Begin in the Left Ventricle as an oxygenated blood cell.
b. Travel through the Aorta.
c. After passing through the aorta  carry your oxygenated blood to the muscles.
d. From the muscles, carry carbon dioxide loaded blood to the Right Atrium.
e. From the Right Atrium travel into the Right Ventricle.
f. Then travel through the Pulmonary Artery.
g. From the Pulmonary Artery proceed into the lungs where and exchange carbon dioxide for oxygen.
h. Now, carrying oxygenated blood enter the Left Atrium and you are ready to begin the circulatory cycle again.

5. You are going to have a relay race to see which group can complete the relay in the shortest amount of time.

6. Be prepared to take on the role of a blood cell and know exactly where to travel in the circulatory system. Proceed, one blood cell (an actual person) at a time. One student (blood cell) must go through the entire circulatory system before the next blood cell may continue. You will be timed  Each blood cell should take about 20 to 25seconds to complete the circuit.

7. Link together (3-4persons) to form a blood clot and traverse the course. What are the health impacts of blood clots? What happens if the left ventricle pushes blood cells out inefficiently (i.e., too slow)? if the valves between the heart chambers allow back flow, rather than control flow in one direction? if the vessels or valves collect deposits that narrow or restrict them?

Wrap-up Session

What factors do you think might affect the efficiency of circulation in real bodies?
What do you think might be the effect of zero gravity (as experienced in space flight) on the circulatory system?

More Activity
1. Write a creative story following a red blood cell though the circulatory system. Include the major parts of the circulatory system as characters in the story. Do not deviate from the true path a blood cell travels.