Blood Flow Through the Heart Mrs. Mullings

Objective You will be able to trace the pathway of blood through the heart

Blood Flow- Pulmonary Circuit Functions as double pump Right side works as pulmonary circuit pump, receiving oxygen-poor blood from the superior and inferior vena cavae Then pumped into the pulmonary arteries, which lead into lungs, where the blood becomes oxygenated Oxygen rich blood then returned to left atria via the pulmonary veins

Blood Flow- Systemic Circuit Blood returned to the left side of the heart is pumped out the aorta, from which the systemic arteries branch and supply all body tissues Oxygen poor blood then returned to heart by systemic veins by way of draining into superior and inferior vena cavae

Functions of Circulation Systems Pulmonary Circulation- carries blood to the lungs for gas exchange and then back to the heart for pumping Systemic Circulation- supplies oxygen and nutrient rich blood to all body organs Left ventricle walls substantially thicker than the right and is more powerful because it is the “super pump” of the heart

Blood Movement through Valves- AV valves Opening and closing of valves a result of pressure gradients When ventricles are relaxed and the pressure is low, the AV cusps hang open, allowing blood flow AV valves are open during heart relaxation and closed when the ventricles are contracting

Blood Movement through Valves- Semilunar Semilunar valves are closed during heart relaxation and are forced open when the ventricles contract When ventricles full of blood, the internal pressure rises and closes the valves, prohibiting blood flow back into the atria As pressure rises in contracting ventricles, it exceeds the pressure downstream from it and the pulmonary trunk and aorta- the ventricular blood then forces the pulmonary and aortic valves open and blood is ejected from the heart

Steps for Blood Flow Through the Heart Blood returns to the heart through the superior and inferior vena cavae and enters the R atrium Blood flows through the R AV valve (TRICUSPID) And into the R Ventricle When R ventricle contracts, the tricuspid valve closes and blood is forced through the pulmonary semilunar valve

Steps for Blood Flow Through the Heart 5) Blood flows into the pulmonary trunk 6) The trunk branches into the R and L pulmonary arteries, which lead to the lungs 7) The oxygen-enriched blood returns by way of the pulmonary veins 8) Which leads to the L atrium

Steps for Blood Flow Through the Heart 9) Blood flows through the BICUSPID valve 10) Into the L Ventricle 11) The L ventricle contracts, forcing the aortic semilunar valve open and expelling the blood through the aortic valve 12) Into the ascending aorta 13) Blood then flows to every organ in the body, unloading its O2, picking up CO2 from the tissues 14) And then returns to the heart via the vena cava

Animation Blood Flow Through Your Heart and Lungs

Practice- Order the Terms in the Correct Sequence Begin with the Superior Vena Cava, and place the following terms in order: Aorta Left AV valve Left atrium Left ventricle Lungs Pulmonary Artery Pulmonary Vein Right Atrium Right Ventricle Right AV Valve

Independent Practice-EXIT TICKET- NO NOTES Trace the steps of the blood on your heart picture, beginning with blood entering the heart from the superior and inferior vena cava. Use red for oxygenated blood and blue for deoxygenated blood. Number the steps 1-14. Describe the steps, in words, on the back of your paper.