|
|
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
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.
Adolescents often feel clumsy during puberty because during this time of development, their hands and feet grow faster than their arms and legs do. The body is therefore out of proportion. One out of five adolescents actually experiences growing pains during this period.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.