photosynthesis is a chemical process through which plants, some bacteria and algae, produce glucose and oxygen from carbon dioxide and water, using only light as a source of energy. photosynthesis is an important life reaction because it produces oxygen for all living organisms on earth also the energy we take in from food we eat 1st came from leafy green plants that absorbed energy from the sun .Without sunlight and plants, the Earth would become an inhospitable place unable to support air-breathing animals and humans.
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Photosynthesis is critical for the existence of the vast majority of life on Earth, photosynthetic organisms form the base of Earth’s food webs and are consumed directly or indirectly by all higher life-forms. If photosynthesis ceased, there would soon be little food and life on earth.