1. Blood Flow Through the Heart
Mrs. Mullings

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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. Animation
Blood Flow Through Your Heart and Lungs

12. 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

13. 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 Describe the steps, in words, on the back of your paper.