the valves as blood passes through them. Lastly, it serves as an electrical insulator between atria and ventricles, via the interatrial & interventricular septum’s. Papillary muscles & Chordea Tendinae: the papillary muscles lie in the walls of the ventricles, while the chordae tendinae stretch out from the inner walls to the valve cusps to prevent eversion of the valves into the atria. Opening & closing of heart valves is not dependent on the fibrous skeleton, but on the pressure differences created by the blood on either side of the valve.
Circulation of Blood
Systemic and Pulmonary Circulation are two closed but interconnected circuits the heart pumps blood into with each beat.
Systemic - The left side of the heart is the “Systemic Pump”
1. The left atrium of heart receives bright red oxygenated blood from the lungs via the pulmonary veins. 2. Blood enters the left ventricle through the Bicuspid Valve. 3. Left Ventricle ejects the blood through the aortic valve into the aorta. 4. From the aorta, blood divides into separate streams and systemic arteries to carry oxygen to all organs throughout the body (except for the alveoli of lungs). 5. Arteries become smaller diameter arterioles, which finally become beds of systemic capillaries where exchange of nutrients and gases occurs.
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