The walls of the heart are made from cardiac muscle, it is made of three layers, epicardium, myocardium and the endocardium. The left side of the heart deals with oxygenated blood and the right side with deoxygenated blood. The heart has 4 chambers pumping blood around the body, the left and right side each have an upper chamber called the atrium and a lower chamber called a ventricle, blood flows from an atrium into a ventricle through a valve called a cuspid valve.
Veins bring the blood to the arteries and take blood away from the ventricles, the valves that are in the beginning of the arteries leaving the ventricles are called semi-lunar valves. The semi-lunar valves and the cuspid valve make sure that the blood only flows through the heart in one direction.
When the heart has been filled up and emptied this is called the cardiac cycle. During this cycle each chamber goes through two phases. Diastole and systole.
Diastole is when the wall relaxes and the chamber gets bigger and fills with blood.
Systole is when the it contracts getting smaller and forcing the blood out.
Cardiac cycle
Deoxygentated blood enters the right atrium thorough the vena cava, it is then pumped down the tri-cuspid valve and enters the right ventricle, the blood is then pumped up through the pulmonary valve towards the lungs in the pulmonary artery. The blood is now oxygenated, it now gets transported back to the heart, it does this by entering the pulmonary vein and into the left atrium, from here it goes through the bicuspid valve into the left ventricle. It then gets pumped through the Aortic (semi-lunar) valve and exits the heart out of the aorta and goes to the cells that require oxygen, the process then starts over again.
Veins bring the blood to the arteries and take blood away from the ventricles, the valves that are in the beginning of the arteries leaving the ventricles are called semi-lunar valves. The semi-lunar valves and the cuspid valve make sure that the blood only flows through the heart in one direction.
When the heart has been filled up and emptied this is called the cardiac cycle. During this cycle each chamber goes through two phases. Diastole and systole.
Diastole is when the wall relaxes and the chamber gets bigger and fills with blood.
Systole is when the it contracts getting smaller and forcing the blood out.
Cardiac cycle
Deoxygentated blood enters the right atrium thorough the vena cava, it is then pumped down the tri-cuspid valve and enters the right ventricle, the blood is then pumped up through the pulmonary valve towards the lungs in the pulmonary artery. The blood is now oxygenated, it now gets transported back to the heart, it does this by entering the pulmonary vein and into the left atrium, from here it goes through the bicuspid valve into the left ventricle. It then gets pumped through the Aortic (semi-lunar) valve and exits the heart out of the aorta and goes to the cells that require oxygen, the process then starts over again.
CGP NOTES.
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