Mouth sores and inflammation (stomatitis) vary in appearance and size and can affect any part of the mouth, inside and outside. People may have swelling and redness of the lining of the mouth or individual, painful ulcers. An ulcer is a hole that forms in the lining of the mouth when the top layer of cells breaks down. Many ulcers appear red, but some are white because of dead cells and food debris inside the center portion.
Among different parts of circulatory system, heart is considered the chief organ. Beating about 1.6 billion times in the average lifespan of a human being, it never gets tired or stops working for a moment till death.
Coordinated contractions of cardiac muscle cells in the heart propel blood out of the atria and ventricles to the blood vessels of the left/body/systemic and right/lungs/pulmonary circulatory systems. This complex mechanism illustrates systole of the heart.