Green Plants do Photosynthesis in day during presence of sunlight and intake C02 to produce O2. In night, Plants do respiration and intake 02 to produce C02. If there will be no animal then Green plants will survive ? Because Earth is like ball, Plants will do photosynthesis=respiration (day=night) and produce oxygen=carbon dioxide. Then from where the oxygen we use comes, and CO2 we release goes ? I will be thankful to you if you answer me or find my mistake.