The Circulatory System 6th Grade Health

Learning Target: Success Criteria: To be successful I will know: I will learn about the Circulatory System. Success Criteria: To be successful I will know: The main parts of the Circulatory System, the importance of each and be able to list/label them. The four things that make up blood.

What is it? It's a big name for one of the most important systems in the body. Made up of the heart, blood and blood vessels, the circulatory system is your body's delivery system. Blood moving from the heart, delivers oxygen and nutrients to every part of the body. On the return trip, the blood picks up waste products so that your body can get rid of them.

Words you need to know… Arteries are tubes that carry blood away from the heart. Veins are tubes that return blood to the heart. Capillaries connect arteries and veins. They are tiny tubes that exchange food, oxygen and wastes between blood and body cells. Pulmonary circulation is the movement of blood between the heart and lungs. Coronary circulation is the movement of blood from within the heart chambers to the heart tissues themselves. Systemic circulation is the movement of blood between the heart and the rest of the body.

Blood contains four major parts: Red blood cells - carry oxygen (O2) from your lungs to your body cells and carbon dioxide (CO2) from your body cells back to your lungs to be exhaled Platelets - help clot blood White blood cells - fight germs that infect the body Plasma - a yellowish liquid that consists mostly of water Red Blood Cells White Blood Cells

What about your heart? About the size of your clenched fist, your heart is a muscle. It contracts and relaxes some 70 or so times a minute at rest -- more if you are exercising -- and squeezes and pumps blood through its chambers to all parts of the body. It does this through an extraordinary collection of blood vessels.

Oxygen-poor blood (shown in blue) flows from the body into the right atrium. Blood flows through the right atrium into the right ventricle. The right ventricle pumps the blood to the lungs, where the blood releases waste gases and picks up oxygen. The newly oxygen-rich blood (shown in red) returns to the heart and enters the left atrium. Blood flows through the left atrium into the left ventricle. The left ventricle pumps the oxygen-rich blood to all parts of the body.

Your Blood Stream… Your blood travels through a rubbery pipeline with many branches, both big and small. Strung together end to end, your blood vessels could circle the globe 2 1/2 times! The tubes that carry blood away from your heart are called arteries. They're hoses that carry blood pumped under high pressure to smaller and smaller branched tubes called capillaries. The tubes that more gently drain back to the heart are veins.

How does your blood get oxygen? When you inhale, you breathe in air and send it down to your lungs. Blood is pumped from the heart to your lungs, where oxygen from the air you've breathed in gets mixed with it. That oxygen-rich blood then travels back to the heart where it is pumped through arteries and capillaries to the whole body, delivering oxygen to all the cells in the body -- including bones, skin and other organs. Veins then carry the oxygen-depleted blood back to the heart for another ride.

Blood circulation: Red = oxygenated Blue = deoxygenated

Your heart will beat about 42,075,904 beats per year and approximately 3 billion times over your lifetime!

The aorta, the largest artery in the body, is almost the diameter of a garden hose. Capillaries, on the other hand, are so small that it takes ten of them to equal the thickness of a human hair. Your body has about 5.6 liters (6 quarts) of blood. This 5.6 liters of blood circulates through the body three times every minute. In one day, the blood travels a total of 19,000 km (12,000 miles)--that's four times the distance across the US from coast to coast.

The heart pumps about 1 million barrels of blood during an average lifetime--that's enough to fill more than 3 super tankers. lub-DUB, lub-DUB, lub-DUB. Sound familiar? If you listen to your heart beat, you'll hear two sounds. These "lub" and "DUB" sounds are made by the heart valves as they open and close.

What’s your type? A, B, AB and O blood types are determined by the presence or absence of antigens (specific chemicals) on the red blood cells Negative (-) or positive (+) blood types are determined by whether or not a chemical called the Rh factor is present on the red blood cells. If someone has this chemical on his red blood cells, then his blood type is positive (+), if he doesn't, then his blood type is negative (-)

Interesting Facts… The body of an adult contains over 60,000 miles of blood vessels! An adult's heart pumps nearly 4000 gallons of blood each day! Your heart beats some 30 million times a year! The average three-year-old has two pints of blood in their body; the average adult at least five times more! A "heartbeat" is really the sound of the valves in the heart closing as they push blood through its chambers. Blood CIRCULATES--circles--all around your body in about one or two minutes.

Try this… Hold out your hand and make a fist. If you're a kid, your heart is about the same size as your fist, and if you're an adult, it's about the same size as two fists. Your heart beats about 100,000 times in one day and about 35 million times in a year. During an average lifetime, the human heart will beat more than 2.5 billion times Put your hand on your heart. Did you place your hand on the left side of your chest? Many people do, but the heart is actually located almost in the center of the chest, between the lungs. It's tipped slightly so that a part of it sticks out and taps against the left side of the chest, which is what makes it seem as though it is located there.

Try This… Give a tennis ball a good, hard squeeze. You're using about the same amount of force your heart uses to pump blood out to the body. Even at rest, the muscles of the heart work hard--twice as hard as the leg muscles of a person sprinting. Feel your pulse by placing two fingers at pulse points on your neck or wrists. The pulse you feel is blood stopping and starting as it moves through your arteries. As a kid, your resting pulse might range from 90 to 120 beats per minute. As an adult, your pulse rate slows to an average of 72 beats per minute.

Click on the link below to watch a short video clip… http://kidshealth.org/kid/htbw/_bfs_CSmoviesource.html