The term photosynthesis has a connotation of meaning "putting
together with light". The actual definition of photosynthesis is the process through
which light energy, water, and carbon dioxide are converted to
carbohydrates and oxygen in the presence of chlorophyll. Chemically
H20 + CO2 + light energy ------>C3H6O3 + O2
Photosynthesis is necessary to produce the carbohydrate which can be stored or used in cellular respiration.