Photosynthesis

The leaves or green part of the plant cells consist of a special cell organelle known as chloroplast. The chloroplasts are organelles present in every plant cell inside which the thylakoids are stacked. Thylakoids are sub cellular structures that are bound by a membrane. The thylakoids membrane possesses pigment molecules called as chlorophylls. Chlorophyll is the green pigment that comprises of Porphyrin rings with a magnesium ion in the middle. Chlorophyll molecules exist in & around the picture systems I & II that are obtainable in the thylakoid membranes. Chlorophyll molecule acts as the reaction middle of picture method I & II. The reaction middle of picture method I absorbs light of particular wavelength (680nm) & the other middle absorbs another wavelength of light (700nm). The chlorophyll in the picture method II absorbs electron given out from splitting of water. Chlorophyll from picture method I take the electron that has travelled through lots of electron transporters in the picture method II. The electron transfers across lots of electron transporting substances which get reduced & oxidized while accepting & donating electron. The method of electron transport aids in release of ATP & NADPH molecules which is called as Assimilatory power. The assimilatory power is useful as the source of energy for the dark reaction to be initiated & carried out.

Plants synthesize their food by themselves & hence they are termed as "autotrophs". The leaves & stems in most of the plants except in few crotons appear green in color. The parts of the plant which appears green in color contribute for synthesis of sugars. The synthesis of sugars is carried out by the method called photosynthesis. Photosynthesis is the method of synthesizing the food materials in the plant with the help of carbon-di-oxide, water & sunlight. The whole method is divided in to light reaction & dark reaction. Light reaction attained this name, as it involves sunlight releasing photons which participate in the first step of the reaction. The energy from photons is absorbed by the water molecule to get split in to electron, hydrogens & oxygen. The oxygen atom released from water will be later converted to oxygen molecule in the electron transport chain of plant respiration.

Dark reaction is the series of reaction mechanisms that involve various carbon compounds getting inter converted by absorbing the energy & releasing at the finish, glucose molecules. The glucose molecules are the source of food for the plant. They are utilized in the respiration as substrate. Dark reaction does not need any light or energy. It makes use of precursors that are released from light reaction & prepare the hexoses.