 The Heart  Blood Vessels(veins, arteries, etc.)  Blood also plays a very important role

 Artery-the type of blood vessel that carries blood away from the heart  Aorta- The largest artery in the body  Red Blood Cell-a type of blood cell that carries oxygen to other body cells  White Blood Cell- the blood cell that fights germs

 Vein – The type of blood cell that carries blood back to the heart  Capillary- a small blood vessel where nutrients, oxygen, and waste pass through  Heart- an organ of blood circulation  Platelet – a part of the cell that helps stop bleeding

 Plasma- The watery part of the blood cell that receives nutrients and waste  Circulatory System- The system of blood, vessels and the heart  Atrium- spaces at the top of the heart that receive blood from the body  Ventricle- spaces in the bottom of the heart that pump blood out of the heart

 Cardiovascular System- a collection of organs that transport blood to and from the your body’s blood cells; the organs in this system include the heart, arteries, and veins.  Pulmonary Circulation- the circulation of blood between the heart and lungs.  Blood- A connective tissue that is made up of two types of cells, cell parts, and plasma.

 Systemic Circulation- the circulation of blood between the hear and the body(excluding the blood)  Blood Pressure- the amount of force exerted by blood on the inside walls of the blood vessel

 There are 4 different types of blood. A, AB, B, and O. O is the universal donor, which means that a person with that can give blood to any type of blood.  You have about 5 liters of blood going through your circulatory system at all times.

 There are 2 different types of blood cells. Red Blood Cells and White Blood Cells.  Red Blood Cells supply your blood with oxygen. Each blood cell contains a protein called hemoglobin, this gives them they’re red color and carries oxygen the cells in the body.  White Blood Cells help protect you from viruses by releasing antibodies, which help destroy pathogens  Blood cells are made in the bones.

 Platelets are tiny particles.  They are pieces of larger cells found in bone marrow.  They only last for 5 to 10 days but they are an important part of the blood.  When you cut or scrape your skin you bleed because blood vessels have been opened, platelets clump and reduce blood loss.

 Blood enters the left atrium first. It receives oxygen-rich blood from the lungs.  When the atria contract, blood is squeezed into the ventricles.  Blood from the right ventricle goes to the lungs. Blood from the left ventricle goes to the rest of the body.

The blood vessels go to every organ. They also work close with the white and red blood cells. The blood vessels carry them throughout the body to fight off diseases and give blood to your organs.

 The heart pumps oxygen rich blood through arteries, arterioles, and capillaries to all of the cells in the body, and oxygen poor blood is pumped back, through veins and venules. The heart then pumps the oxygen poor blood to the lungs, which transforms the blood into oxygen rich blood, and the process starts all over again.

 Oxygen rich blood from the lungs enters the left atrium, while the right atrium receives oxygen poor blood from the body.  The blood is squeezed into the ventricles when the atria contract.  The blood is pushed out of the heart when the atria relax. The blood that was in the right ventricle goes to the lungs and the blood in the left ventricle goes to the rest of the body.  The lub-dub sound is the closing and opening of valves to prevent the blood from going backwards.

 This is a picture of the heart which shows both the inside and outside of the heart.  Note the right and left atriums and ventricles.

 Between 8 a.m. and 9 a.m. is the time when most heart attacks happen  For a typical human, the heart will beat 2.5 billion times in a lifetime  The heart can beat 100,000 times in a day  The heart can beat up to 35 million times a year  It has been discovered that boys with longer middle fingers are less likely to have a heart attack  The heart is made mostly of muscle, and it is strong enough to lift about 3,000 pounds  The hearts of women beat faster than that of men  The first successful heart transplant was performed in Cape Town, South Africa

 The heart can pump up to one million barrels of blood in a lifetime  Laughing can make your heart beat faster for up to forty-five minutes  A kitchen faucet would need to be on all the way for at least 45 years to equal the amount of blood that the heart pumps in a lifetime  If you stretched out all the vessels in the cardiovascular system, it would reach over miles, which would reach around earth twice!

Have you ever gone to the doctor and got your pulse checked. Well he touched your artery. The faster your heart pumps the more blood rushes through your arteries. If you ever cut your artery you have a very high chance of dying. Your heart beats over 30 million times in 1 year. If you would stretch your blood vessels it would cover 60, ,000 miles