<P> Jan van Helmont began the research of the process in the mid-17th century when he carefully measured the mass of the soil used by a plant and the mass of the plant as it grew . After noticing that the soil mass changed very little, he hypothesized that the mass of the growing plant must come from the water, the only substance he added to the potted plant . His hypothesis was partially accurate--much of the gained mass also comes from carbon dioxide as well as water . However, this was a signaling point to the idea that the bulk of a plant's biomass comes from the inputs of photosynthesis, not the soil itself . </P> <P> Joseph Priestley, a chemist and minister, discovered that, when he isolated a volume of air under an inverted jar, and burned a candle in it, the candle would burn out very quickly, much before it ran out of wax . He further discovered that a mouse could similarly "injure" air . He then showed that the air that had been "injured" by the candle and the mouse could be restored by a plant . </P> <P> In 1778, Jan Ingenhousz, repeated Priestley's experiments . He discovered that it was the influence of sunlight on the plant that could cause it to revive a mouse in a matter of hours . </P> <P> In 1796, Jean Senebier, a Swiss pastor, botanist, and naturalist, demonstrated that green plants consume carbon dioxide and release oxygen under the influence of light . Soon afterward, Nicolas - Théodore de Saussure showed that the increase in mass of the plant as it grows could not be due only to uptake of CO but also to the incorporation of water . Thus, the basic reaction by which photosynthesis is used to produce food (such as glucose) was outlined . </P>

What are organisms that carry out photosynthesis called