Definition of ribbon. 1  1a : a flat or tubular narrow closely woven fabric (as of silk or rayon) used for trimmings or knittingb : a narrow fabric used for tying packagesc : a piece of usually multicolored ribbon worn as a military decoration or in place of a medald : a strip of colored satin given for winning a place in a competition.
Photosynthesis is the process by which organisms that contain the pigment chlorophyll convert light energy into chemical energy which can be stored in the molecular bonds of organic molecules (e.g., sugars). Photosynthesis powers almost all trophic chains and food webs on the Earth.
Polar Covalent Bonds. There are two types of covalent bonds: polar and nonpolar. In a polar covalent bond, the electrons are unequally shared by the atoms because they are more attracted to one nucleus than the other .