Each side of the heart comprises 2 chambers - the upper chambers are the atria,
and the lower chambers are the ventricles. The left and right sided chambers are
separated by a wall of muscle, called septum.
The right sided chambers
deal with receiving deoxygenated blood from the vena cava, and sending it to the
lungs, via the pulmonary arteries. The left sided chambers receive oxygenated
blood from the lungs, via the pulmonary veins, then pump the blood into the aorta,
to be delivered to the systemic circulation.
|Tricuspid||Regulates blood flow between the right atrium and right
|Pulmonary||Controls blood flow from the right ventricle into the
pulmonary arteries, which carry deoxygenated blood to the lungs.|
|Bicuspid||Aka the Mitral valve, lets oxygenated blood from
the lungs pass from the left atrium into the left ventricle.|
|Aortic||Allows oxygenated blood to pass from the left ventricle
into the aorta, from whence it is distributed to the whole body.|
Electrical activity in the heart follows the Cardiac Cycle...
- The Sinoatrial Node (pacemaker) in the right Atrium creates an electrical signal.
- The electrical signal flows through both Atria, stimulating the Atria to
contract and push blood into the ventricles.
- When the electrical signal reaches the Atrioventricular Node, it pauses to give
the ventricles time to fill with blood.
- The electrical signal spreads through the Bundle of His, then to the
Purkinje Fibres, which are located in the cardiac muscle. This causes the
ventricles to contract and push blood out to the pulmonary and systemic