Almost  all the living beings depend upon plants which perform photosynthesis plants make use of chlorophyll,water,co2,sunlight which is converted to chemical energy and reduction of co2 to carbohydrates takes place which serves as food for all the living beings there are mainly 2 types they are light dependent which occurs in grana of chloroplast and light independent reaction in stoma so it promotes the sustainance of life on is the only process which adds free oxygen and food material so it is appreciable.

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