1. The Cardiovascular System

2. Composed of the HEART and all of the blood vessels of the body.

3. Functions… To circulate blood
Maintain an internal environment in which all cells of your body are nourished.

4. Carbon Dioxide is delivered to the lungs
As your heart pumps…
Blood vessels carry oxygen and nutrients to body cells.
Carbon dioxide is carried, along with waste matter, from your cells.
Carbon Dioxide is delivered to the lungs
Waste products are delivered to the kidneys for removal from the body.

5. Structure The cardiovascular system consists of: The heart Blood
Blood vessels
Arteries
Capillaries
Veins
These all transport blood throughout the body

6. The HEART
Along with the brain, it is one of the most important organs in the body.
The pump that makes the cardiovascular system work
NEVER RESTS
Made up of:
Muscle tissue called MYOCARDIUM
Contracts and relaxes constantly and rhythmically.

7. Chambers of the Heart There are 4 chambers in the heart
Two atriums
The two smaller chambers
Two ventricles
The two lower, larger chambers
A wall of tissue, called the SEPTUM, separates the right and left sides of each.

8. At the top of the right atrium is an area of muscle that acts as a natural pacemaker for the rest of the heart.
Regular electrical impulses from this area stimulate the muscles of each atrium to contract.
Forcing blood into the ventricles.
This then sends electrical impulses to the area between the two ventricles and causes them to contract.
This sends the blood out of the heart.

9. Valves
Valves between the atria and ventricles allow blood to flow through the chambers of the heart.
THESE ARE “ONE-WAY” VALVES
Atria to ventricles
The sound you hear as the heart beat is the closing of these valves.

10. Circulation in the heart
Vena Cava
Blood that has been depleted of oxygen but contains carbon dioxide and waste matter is carried to the heart by two large blood vessels called the vena cava.
Enters the right atrium and is transferred to the right ventricle, then to the lungs
In the lungs the blood releases the carbon dioxide and picks up oxygen from inhaled air.
This newly oxygenated blood is returned from the lungs to the left atrium of the heart.
The left atrium pumps the oxygenated blood into the left ventricle, which then pumps the blood out of the heart to the rest of the body through the large artery called the AORTA.

11. Blood Delivers: Carries away waste that the cells produce Plasma
Oxygen
Hormones
Nutrients
Carries away waste that the cells produce
Plasma
The fluid in which other parts of the blood are suspended
Mostly water

12. Blood Red blood cells White blood cells
Transport oxygen to the cells and tissues
Formed in bone marrow
Contain hemoglobin
The oxygen carrying protein in blood.
White blood cells
Main role is to protect the body against infection and fight infection when it occurs.
Part the of the immune system
Produced in bone marrow

13. Blood Vessels
A network of more than 60,000 miles of blood vessels that transport blood.
Three main types of blood vessels
Arteries
Capillaries
Veins

14. Arteries The blood vessels that carry blood AWAY from the heart.
Have thick elastic walls with smooth muscle fibers
Pulmonary arteries
Carry deoxygenated blood from the right ventricle to the lungs
Systemic arteries (aorta)
Carry oxygenated blood from the left ventricle to all areas of the body.

15. Capillaries
Are small vessels that carry blood between arterioles and small vessels called VENULES
Form extensive networks in tissues and organs
The exchange of gases, nutrients and wastes between blood and cells takes place through the ultra-thin walls of the capillaries.
Play a role in body temp. regulation.

16. Veins The blood vessels that RETURN blood to the heart. Vena cava
Carry deoxygenated blood from the body to the right atrium of the heart
Pulmonary veins
Carry oxygenated blood from the lungs to the left atrium.
Have valves that prevent backflow.

17. Platelets The cells that prevent the body’s loss of blood.
These gather at the site of an injury and release chemicals that make them sticky, causing them to clump together with other cells.
The chemicals release stimulate FIBRIN to form.
Fibrin are small, thread-like fibers
SCAB