the blood group whose red cells carry neither the A nor B antigens; "people with type O blood are universal donors"
a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 28 percent of the atmosphere by volume; the most abundant element in the earth's crust
the 15th letter of the Roman alphabet
a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth''s crust
the blood group whose red cells carry neither the A nor B antigens
a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
