Respiration occurs in all living things--including plants. Respiration can be aerobic(with oxygen present) or anaerobic(without oxygen). It is a process by which chemical energy in food is released for use in the cell in the form of ATP. In aerobic respiration, glucose is converted to carbon dioxide, water and 36 ATP, a high energy compound used by cells for energy. An example of anaerobic respiration is when yeast cells ferment glucose to form alcohol and carbon dioxide, both waste products and 2 ATP. Photosynthesis is the process by which green plants and algae convert carbon dioxide and water, in the presence of light energy absorbed by the pigment chlorophyll, into glucose(chemical energy) and oxygen(waste product). Respiration releases the energy stored in the chemical bonds of glucose and photosynthesis stores light energy in the form of chemical energy--glucose.