Unlike animals, plants are unable to capture or gather their food, they have to make it themselves. They do this during the process of photosynthesis, which means ‘putting together by light’. Plants collect energy from the Sun and use it to turn water and carbon dioxide into a simple sugar called glucose. This is then used to fuel the plant’s cells and to make starch and cellulose. This all takes place not just within the leaf structure of plants, but in all green plant tissue cells. Within these tissues, there are small particles called chloroplasts which contain pigments, including the green pigment chlorophyll. When light falls on these, they trap and absorb the energy. A series of complex chemical reactions then take place during which water molecules are split apart into hydrogen and oxygen atoms. The hydrogen atoms combine with carbon
dioxide to make glucose and oxygen is given off as a waste product. We cannot normally see this release of oxygen, but plants whose natural habitat is in water sometimes form bubbles on their leaves during the process of photosynthesis. Some of the water taken in by plants though their root system is used in the process of photosynthesis but most of it evaporates through the leaves, escaping together with gases through small holes called stomata.
