|
|
The familiar sounds of your heart are made by the heart's valves as they open and close.
Anti-aging claims should not ever be believed. There is no supplement, medication, or any other substance that has been proven to slow or stop the aging process.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
During pregnancy, a woman is more likely to experience bleeding gums and nosebleeds caused by hormonal changes that increase blood flow to the mouth and nose.