<span>The cycles would eventually come to an end. If the sun were to burn out, the Earth would lose the energy and heat from the sun and soon lose its own heat and energy and fall apart into space. The magnetism would soon become demagnetized, plates would stop moving, trees would die, life etc. no more O2, CO2, cycle and all others would fade.</span>
Well all reactions need energy to start it. The light is the energy that the reaction requires to start it. Sunlight also has no mass in the first place so laws of conservation of mass don't apply to it.
