The energy source in photosynthesis is

a. light energy.

c. heat energy.

b. chemical energy.

d. kinetic energy.

A, light energy from the sun is absorbed by the plant and when the light energy reaches the grana it is absorbed by the chlorophyll molecules in the chloroplast. The chemical energy is then used to create an energy rich molecule known as ATP (adenosine triphosphate) and the rest of the light energy absorbed is used for photolysis (the process where H2O molecules are split unto O2 molecules and energy-rich hydrogen molecules) the oxygen is then released into the atmosphere as oxygen and the ATP, H molecules and CO2 from the atmosphere will then be used in the next phase which is the dark phase. This is the Light phase of photosynthesis