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.
The three types of photosynthesis are C3, C4 and CAM photosynthesis. The definition of photosynthesis and the general equation can be found under Overview of Photosynthesis. Plants perform photosynthesis because it generates the food and energy they need for growth and cellular respiration. It is important to note that not all plants photosynthesize. Some are parasites and simply attach themselves to other plants and feed from them.