Share Your PPT File. The leaves have a green pigment called chlorophyll. Thus the fate of different molecules can be summarized as follows: Synthesis of ATP from ADP and inorganic phosphate (pi) in presence of light in chloroplast is known as photophosphorylation. This decline in photosynthesis is called Red drop effect (Emerson’s first experiment). It is the phenomenon of re-radiation of absorbed energy. 5. While the PGA is used up in the Calvin cycle, the phosphoglycolate is dephosphorylated to form glycolate in the chloroplast (Fig. How would you test the presence of starch in leave Give a brief description of the process of synthesis of (b) As electrons move through the photosystems, protons are transported across the membrane. The process of photosynthesis in plants consists of a complex series of biochemical reactions. In respiration, protons accumulate in the inter-membrane space of the mitochondria when electrons move through the ETS. It has been experimentally proved that an increase in carbon dioxide content of the air up to about one per cent will produce a corresponding increase in photosynthesis provided the intensity of light is also increased. Share with your friends. But for the first time Van Neil discovered that the source of oxygen evolution is not carbon dioxide but H2O. When P680 or P700 (special type of chlorophyll a) of two pigment systems receives quantum of light then it becomes excited and releases electrons. Carbon dioxide is absorbed from outside. It was proposed by Melvin Calvin. It means that 8 photons or quantum’s are required to release one molecule of oxygen. Some of the granna lamella are connected with thylakoids of other granna by stroma lamella or fret membranes. The amount of CO2 fixed by a gram of chlorophyll in an hour is called photosynthetic number or assimilation number. Give a brief description of the process of synthesis of food in green plants. Chlorophyll is an essential internal factor for photosynthesis. Give a brief description of the process of synthesis of food in green plants. 3. Photosynthesis Process Step by Step By definition, photosynthesis is a process by which photoautotrophs convert the energy derived from the Sun into usable chemical energy. Therefore, at one time only one factor limits the rate of physiological process. Distinguish between a parasite and a saprotroph. You may wonder how this could be verified; it is simple: immediately after light becomes unavailable the biosynthetic process continues for some time, and then stops. For a complete plant, rate of photosynthesis increases with increase in light intensity, except under very high light intensity where phenomenon of Solarization’ occurs, (i.e., photo-oxidation of different cellular components including chlorophyll). Photorespiration was discovered by Dicker and Tio (1959), while the term “Photorespiration” was coined by Krotkov (1963). 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