Plant primitive plants lacking some tissue types. Plants are photosynthetic, which means that they manufacture their own food molecules using energy obtained from light. The primary mechanism plants have for capturing light energy is the pigment chlorophyll. All green plants contain two forms of chlorophyll, chlorophyll "a" and chlorophyll "b". The latter of these pigments is not found in red or brown algae. The simple equation of photosynthesis is as follows:- 6CO + 6HO → (in the presence of light and chlorophyll) CHO + 6O By means of cells that behave like nerves, plants receive and distribute within their systems information
Thylakoid centers, each consisting of an antenna complex that uses chlorophylls and accessory photosynthetic pigments such as carotenoids and phycobiliproteins to harvest light at a variety of wavelengths. Each antenna complex has between 250 and 400 pigment molecules and the energy they absorb is shuttled by resonance energy transfer to a specialized chlorophyll "a" at the reaction center of each photosystem. When either of the two chlorophyll "a" molecules at the reaction center absorbs energy, an electron is excited and transferred to an electron-acceptor molecule. Photosystem I contains a pair of chlorophyll "a" molecules, designated P700, at its reaction center that