Blood – everyone's got it. In fact, an adult who weighs between 150 and 180 pounds has around 1.2 to 1.5 gallons of blood in their body. This makes up approximately 10% of an adult’s weight. Blood ...

Blood types are a classification of blood based on the antigens present in red blood cells. In the United States, O-positive is the most common blood type, and AB-negative is the rarest. A blood ...

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Learn more. Though cancer can start in any area of the body, the ...