forms over millions of years in the pore spaces of sedimentary rocks from remains of ocean-dwelling phytoplankton; over time it migrates upward toward the highest point in the porous rock because it is less dense than the rock.
Hereditary hemochromatosis (hee-muh-kro-muh-TOE-sus) is a genetic disease that causes the body to absorb and store too much iron. Iron is an important nutrient that our bodies get from food.
Homocystinuria is an autosomal recessive inherited metabolic disorder caused by a defect in an enzyme that converts the amino acid homocysteine to cystathionine, resulting in accumulation of homocysteine in the blood and its excretion in urine.