|
|
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
Earwax has antimicrobial properties that reduce the viability of bacteria and fungus in the human ear.
Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.