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).
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins.eing passive, facilitated transport does not directly require chemical energy from ATP hydrolysis in the transport step itself; rather, molecules and ions move down their concentration gradient reflecting its diffusive nature. Facilitated diffusion is different from free diffusion in several ways.