Introduction Chewing gum in various forms has been around since ancient times. The Greeks chewed sap from the mastic tree, called mastiche. On the other side of the world, the ancient Mayans favored the sap of the sapodilla tree (called tsiclte).
Bioremediation is a waste management technique that involves the use of organisms to remove or neutralize pollutants from a contaminated site.ioremediation may occur on its own (natural attenuation or intrinsic bioremediation) or may only effectively occur through the addition of fertilizers, oxygen, etc., that help encourage the growth of the pollution-eating microbes within the medium (biostimulation).
passive transport, the movement of small molecules across the membrane of a cell by diffusion. Passive transport occurs when the chemicals outside a cell become concentrated and start moving into the cell, changing the intracellular equilibrium. Passive transport is essential to various processes of metabolism, such as the intake of digestive products by the cells lining the intestines.