HOW THE BODY WORKS
We breathe air to get oxygen.
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The oxygen goes into the blood in the lungs
The blood with oxygen travels from the lungs to the heart
The heart is a big pump and it pumps the blood with oxygen to all the parts of the body
The oxygen from the blood goes into the cells of the body
At the same time, the cells put their waste back into the blood
The blood with much less oxygen and the cell’s waste travels back to the heart
The heart pumps this blood back to the lungs to get more oxygen
The cycle starts over when we take another breath
WHAT ARE THE PARTS OF THE HEART?
The heart has a left side and a right side
It is divided into four parts, called chambers
The atria are on top and the ventricles are on the bottom
The left atrium is connected to the left ventricle by the mitral valve
The right atrium is connected to the right ventricle by the tricuspid valve
The aortic valve pumps blood with oxygen from the left ventricle to the body
The pulmonic valve pumps blood from the right ventricle back to the lungs
WHAT IS A HEARTBEAT?
The heartbeat sound lub-dub, lub-dub is caused by the heart valves closing.
The first sound, lub, is caused by the tricuspid and mitral valves closing.
The mitral valve and the tricuspid valve control blood flow from the atria to the ventricles
The second sound, dub, is caused by the aortic and pulmonary valves closing.
The aortic and pulmonary valves control blood flow out of the heart.
HOW DOES THE BLOOD FLOW THROUGH THE HEART?
The heart has a right side and a left side
Blood enters the heart in the atria
The left atria has blood with lots of oxygen- this blood comes from the lungs
The blood from the left atria goes through the mitral valve and into the left ventricle
The blood from the left ventricle goes though the aortic valve and is pumped to the body
The right atria has blood that comes from the body. It has only a little oxygen in it. Blood from the right atria goes through the tricuspid valve and into the right ventricle
The blood from the right ventricle is pumped through the pulmonic valve back to the lungs to get more oxygen
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In order to work right, the heart needs time to fill and enough strength to pump
WHAT MAKES THE HEART PUMP?
The heart is controlled by an electrical signal
The signal starts in in SA node - also called the pacemaker of the heart
The electrical signal travels to the atria and they contract
Then the electrical signal travels to the ventricles and they contract
When the heart is not pumping, it is relaxed and filling with blood
We can tell if the heart’s electrical system is working right by looking at an EKG
WHAT IS A PULSE?
Your pulse measures the rate your heart is beating.
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The easiest way to test your pulse is to get your heart rate up. Run around for a few minutes or do jumping jacks.
Stop moving and put two fingers lightly on the side of your neck. Can you feel your pulse? Count how many times you feel your pulse in a minute.
WHAT MAKES THE HEART NOT WORK?
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The heart can’t fill and pump blood the right way
Blood supply to heart is blocked
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Electrical system isn’t right
Sometimes there is a problem with more than one of these at the same time
