The aim of this lecture is to present on overview of Photosynthesis. Carbon dioxide and water are taken in by plants. Plants absorb light energy and convert it to a usable form- ATP. Energy is used to “fix” carbon dioxide into sugar molecules- Chemical energy. Sugar is converted to starch and stored for use by the plant, and by animals when they eat plants. Here also briefly present on Light (dependent)Reactions and Chlorophyll. Chlorophyll molecules are embedded in the thylakoid membrane.