Antoine-Laurent Lavoisier conducts an experiment on human respiration in this drawing made by his wife, who depicted herself at the table on the far right. Image provided by Edgar Fahs Smith Memorial Collection, Department of Special Collections, University of Pennsylvania Library.		Respiration and photosynthesis In 1777 Antoine-Laurent Lavoisier (1743–1794) determined that respiration was an oxidation process analogous to combustion. In 1779 Jan Ingenhousz (1730–1799) showed that photosynthesis is the reverse process of respiration: while respiration involves the combination of oxygen with carbon to form carbon dioxide, photosynthesis breaks carbon dioxide back down into oxygen and carbon.