Respiration vs Photosynthesis

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Photosynthesis vs Respiration To obtain vital energy needed for life, organisms depend on the processes of both respiration and photosynthesis. The two processes share the same function of changing energy from one form to another, there are some similarities, but there are many differences between respiration and photosynthesis, such as the input and output molecules and cellular location. Photosynthesis is the process in which energy from sunlight is utilised to make the molecule glucose from water and carbon dioxide. Water is sourced from the surrounding soil, the carbon dioxide is diffuses into the leaf via the stoma. Light energy from the sun is converted into chemical energy in the form of glucose. Photosynthesis occurs in a series of reactions but the overall equation is: 6CO2 + 6H2O + energy C6H12O6 + 6O2. Energy is stored in the glucose until the plant releases it by respiration. Respiration is the process in which energy stored in glucose molecules is released in the form of ATP. Respiration complex process containing 4 reaction stages, but can be summarised as: C6H12O6 + 6O2 6CO2 + 6H2O + ATP. ATP can then be broken down quickly to release energy when energy is required by the cell. As shown in the written equations above, the chemical equations of aerobic respiration and photosynthesis are opposites. The products of respiration, are the reactants for photosynthesis and vice versa. Respiration can occur at all times in a cell because no stages in the process require sunlight. Whereas photosystem II requires sunlight for the photolysis of water and to excite electrons, so photosynthesis can only happen in a cell when sunlight is present. For example, photosynthesis cannot take place during the night but respiration can. Both processes take place inside the cells. The site of photosynthesis is
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