1. The Cardiovascular System The cardiovascular system transports materials to and from your cells.The cardiovascular system transports materials to and from your cells. The cardiovascular system is made up of three parts: blood, the heart, and blood vessels.The cardiovascular system is made up of three parts: blood, the heart, and blood vessels.

2. Blood is a connective tissue made up of red blood cells, white blood cells, platelets and plasmaBlood is a connective tissue made up of red blood cells, white blood cells, platelets and plasma Plasma is the fluid part of blood.Plasma is the fluid part of blood. Red blood cells, white blood cells, and platelets float in the plasmaRed blood cells, white blood cells, and platelets float in the plasma

3. Red blood cells supply your cells with oxygenRed blood cells supply your cells with oxygen Each RBC contains a protein called hemoglobinEach RBC contains a protein called hemoglobin Hemoglobin gives blood its red colorHemoglobin gives blood its red color

4. White blood cells destroy pathogensWhite blood cells destroy pathogens Some WBC’s squeeze out of vessels and move around in tissues, searching for pathogens. When they find a pathogen, they engulf itSome WBC’s squeeze out of vessels and move around in tissues, searching for pathogens. When they find a pathogen, they engulf it Other WBC’s release chemicals called antibodies, which help destroy pathogens.Other WBC’s release chemicals called antibodies, which help destroy pathogens.

5. Platelets Platelets are pieces of larger cells which release chemicals in damaged vessels and cause fibers to formPlatelets are pieces of larger cells which release chemicals in damaged vessels and cause fibers to form The fibers make a “net” that traps blood cells and stops bleeding.The fibers make a “net” that traps blood cells and stops bleeding. 3- red blood cell 5- platelet

6. Red & White Cells in a blood vessel Blood Cells in a small blood vessel Red Blood Cell White Blood Cell

7. Your heart is about the size of your fist.Your heart is about the size of your fist. The heart pumps oxygen-poor blood to the lungs and oxygen-rich blood to the bodyThe heart pumps oxygen-poor blood to the lungs and oxygen-rich blood to the body

8. Your heart has a left side and a right side that are separated by a thick wallYour heart has a left side and a right side that are separated by a thick wall Each side has an upper chamber and a lower chamberEach side has an upper chamber and a lower chamber Upper chamber is called an atriumUpper chamber is called an atrium Lower chamber is called a ventricleLower chamber is called a ventricle

9. Valves are located between the atria and ventriclesValves are located between the atria and ventricles As blood moves through the heart, the valves close and prevent blood from going backward.As blood moves through the heart, the valves close and prevent blood from going backward.

10. Blood Vessels Blood flows throughout your body in blood vesselsBlood flows throughout your body in blood vessels A blood vessel is a hollow tube that transports bloodA blood vessel is a hollow tube that transports blood There are three types of blood vessels—arteries, capillaries, and veinsThere are three types of blood vessels—arteries, capillaries, and veins

11. Arteries carry blood away from the heart.Arteries carry blood away from the heart. Arteries have thick walls that contain a layer of smooth muscleArteries have thick walls that contain a layer of smooth muscle When blood is pumped out of the heart at high pressure, these thick walls have the strength to withstand it.When blood is pumped out of the heart at high pressure, these thick walls have the strength to withstand it.

13. Capillaries are the smallest blood vessels in your body.Capillaries are the smallest blood vessels in your body. Capillary walls are only one cell thickCapillary walls are only one cell thick No cell in the body is more than three or four cells away from a capillaryNo cell in the body is more than three or four cells away from a capillary

15. Veins carry blood back to the heart.Veins carry blood back to the heart. When skeletal muscles contract, they squeeze nearby veins and help push blood toward the heartWhen skeletal muscles contract, they squeeze nearby veins and help push blood toward the heart

18. If all the blood vessels in your body were strung together, the total length would be more than twice the circumference of the Earth.If all the blood vessels in your body were strung together, the total length would be more than twice the circumference of the Earth.

19. Exercise and blood flow Physical activity causes as much as 10 times more blood to be sent to the muscles than when your body is at rest.Physical activity causes as much as 10 times more blood to be sent to the muscles than when your body is at rest. Less blood is sent to the kidneys and the digestive system so that more blood can go to the skeletal muscles, brain, heart, and lungsLess blood is sent to the kidneys and the digestive system so that more blood can go to the skeletal muscles, brain, heart, and lungs