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The scientist Charles Barnes first used the word 'photosynthesis' in 1893. This word is taken from two Greek words, photos, which means light, and synthesis, which in chemistry means making a substance by combining simpler substances. So, in the presence of light, synthesis of food is called 'photosynthesis'.
6 H 2 O + 6 CO 2 + energy → C 6 H 12 O 6 + 6 O 2 where C 6 H 12 O 6 is glucose (which is subsequently transformed into other sugars , starches , cellulose , lignin , and so forth). The value of the photosynthetic efficiency is dependent on how light energy is defined – it depends on whether we count only the light that is absorbed, and on ...
However, the membrane may be tightly folded into cylindrical sheets called thylakoids, [23] or bunched up into round vesicles called intracytoplasmic membranes. [24] These structures can fill most of the interior of a cell, giving the membrane a very large surface area and therefore increasing the amount of light that the bacteria can absorb. [23]
In oxygenic photosynthesis, the first electron donor is water, creating oxygen (O 2) as a by-product. In anoxygenic photosynthesis, various electron donors are used. Cytochrome b 6 f and ATP synthase work together to produce ATP (photophosphorylation) in two distinct ways.
[2] The main function of PSII is to efficiently split water into oxygen molecules and protons. PSII will provide a steady stream of electrons to PSI, which will boost these in energy and transfer them to NADP + and H + to make NADPH. The hydrogen from this NADPH can then be used in a number of different processes within the plant. [2]
Reaction centers are present in all green plants, algae, and many bacteria.A variety in light-harvesting complexes exist across the photosynthetic species. Green plants and algae have two different types of reaction centers that are part of larger supercomplexes known as P700 in Photosystem I and P680 in Photosystem II.
The evolution of oxygen during the light-dependent steps in photosynthesis (Hill reaction) was proposed and proven by British biochemist Robin Hill. He demonstrated that isolated chloroplasts would make oxygen (O 2) but not fix carbon dioxide (CO 2). This is evidence that the light and dark reactions occur at different sites within the cell. [1 ...
A light-harvesting complex consists of a number of chromophores [1] which are complex subunit proteins that may be part of a larger super complex of a photosystem, the functional unit in photosynthesis. It is used by plants and photosynthetic bacteria to collect more of the incoming light than would be captured by the photosynthetic reaction ...