The Circulatory System Video Introduction (22min)

The Body’s Transport System Made up of the heart, blood and a series of blood vessels. Jobs: 1.Delivers nutrients and oxygen to the body cells. 2.Carries carbon dioxide and other wastes away from the body cells. 3.Protects the body from disease and infection.

The Heart Cardiac muscle – Involuntary like smooth muscle – Reacts quickly & Striated like skeletal muscle – Doesn’t tire Only rests between beats Approximately the size of your fist. Located slightly to the left of your sternum. Pumps approximately 5 L of blood per minute. Heartbeat is controlled by a special tissue – pacemaker. – Sends out signals to the heart muscle that controls contractions.

The Heart Aorta Pulmonary Artery Pulmonary Vein Left Atrium Valves Left Ventricle Superior Vena Cava Pacemaker Pulmonary Artery Pulmonary Vein Right Atrium Right Ventricle Valves Inferior Vena Cava Septum

The Heart Your heart is made up of four chambers: – Two upper chambers – Atrium (Atria = singular) – Two lower chambers - Ventricles The heart is also split into left and right sides – separated by a thick wall of tissue – Septum Blood will never cross between the two sides. As we discuss the heart from now on, YOU will become the doctor and THE HEART will be the patient laying on the operating table. – Left becomes Right and Right becomes Left!!!!!!!

Divisions & Chambers Upper Chambers – Atrium Lower Chambers – Ventricles Right SideLeft Side

Flow of Blood Blood returning to the heart from the head. Blood returning to the heart from the body. Blood leaving the heart -to the head. Blood leaving the heart -to the body. Blood going to the lungs Blood going to the lungs Blood going back to the heart from the lungs Blood going back to the heart from the lungs

Myths about the Color of Blood Is blood really blue? – NO – blood is NOT blue!!!!!! BLOOD IS RED!!!!! – Blood can either be: high in oxygen, brighter red color, or low in oxygen, darker red color. (purple) – The skin changes the way blood looks in the veins to make it look bluer in color.

Right Side I.The Patient’s Right Side of the Heart  Blood is returning to the heart from it’s trip around the body.  Returns to the heart through the Vena Cava  Condition of the blood: o High in Carbon Dioxide o Low in Oxygen

Right Side 1.Right Atrium (RA) – Collecting chamber for blood returning to the heart from the body. 2.Right Ventricle (RV) – Pumping chamber – sends blood to the lungs. – A valve separates the two chambers and prevents blood from flowing backwards

Right Side 3.Blood leaves the heart, through the pulmonary arteries. – Drops off waste gas carbon dioxide. – Picks up new supply of oxygen. 4. Returns to the heart through the pulmonary veins

Left Side I.The Patient’s Left Side of the Heart  Blood is returning to the heart from it’s trip to the lungs.  Condition of the blood: o High in Oxygen o Low in Carbon Dioxide

Left Side 5.Left Atrium (LA) – Collecting chamber for blood coming back to the heart from the lungs. 6.Left Ventricle (LV) – Pumping chamber – pumps blood to the rest of the body. – Six times more powerful than the right ventricle

Leaving the Heart 7.Blood leaves the heart through the largest and strongest blood vessel in the body – Aorta 7. To the Head/Upper Body To the Lower Body Pump Your Blood – Happy Days (4:09 min)