I pretty sure it's the uterus
It can't be released by photosynthesis
Photosynthesis makes the glucose that is used in cellular respiration to make ATP. The glucose is then turned back into carbon dioxide in the process of respiration, which is then used in photosynthesis. While water is broken down to form oxygen in photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water. ATP is manufactured as a result of several processes including fermentation, respiration and photosynthesis.
If we had the same climate every minute of every hour tons of carbon would circulate the earth and climate change would make the polar ice caps melt from all the carbon around
