The Circulatory System Video Introduction (22min)

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

The Heart Cardiac muscle Approximately the size of your fist. 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 Superior Vena Cava Pulmonary Artery Pacemaker Vein Pulmonary Vein Left Atrium Right Atrium Valves Valves Right Ventricle Left Ventricle 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.

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

Two Loop Pathway The flow of blood, through the heart, takes place in a two loop pathway Heart-Lung-Heart Returning from the body Low in Oxygen High in Carbon Dioxide Heart-Body-Heart Returning from the lungs High in Oxygen Low in Carbon Dioxide

Flow of Blood Blood leaving the heart -to the head. Blood returning to heart-lung-heart loop Blood returning to the heart from the head. heart-body-heart loop 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 Blood leaving the heart -to the body. Blood returning to the heart from the body.

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 The Patient’s Right Side of the Heart heart-lung-heart loop 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: High in Carbon Dioxide Low in Oxygen

1. 2. Right Side Right Atrium (RA) Right Ventricle (RV) Function: Collecting chamber Coming from: body Going to: Right Ventricle Oxygen: Low Carbon Dioxide: High Right Ventricle (RV) Function: Pumping chamber Coming from: Right Atrium Going to: Lungs A valve separates the two chambers and prevents blood from flowing backwards. 1. 2.

A Trip to the Lungs = (Pulmonary) Blood leaves the heart, heading to the lungs, 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. 3. 3. 4. 4.

Left Side The Patient’s Left Side of the Heart heart-body-heart loop 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: High in Oxygen Low in Carbon Dioxide

5. 6. Left Side Left Atrium (LA) Left Ventricle (LV) Function: Collecting chamber Coming from: lungs Going to: Left Ventricle Oxygen: High Carbon Dioxide: Low Left Ventricle (LV) Function: Pumping chamber Coming from: Left Atrium Going to: Body Strongest chamber of the heart: Six times more powerful than the right ventricle. 5. 6.

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