During photosynthesis, plants use light energy to synthesize glucose from carbon dioxide. however, plants do not use up energy during photosynthesis; they merely convert it from light energy to chemical energy. this process is an illustration of

the first law of thermodynamics

Glucose, also called grape sugar, blood sugar or corn sugar, is among the simplest and one of the primary naturally occurring sugars. produced naturally by plants as the primary photosynthesis product, it is heavily used by living beings as a main energy source and is necessary for cellular respiration. chemically, it is a monosaccharide carbohydrate and serves as a building block for complex sugars like starch.

Sorry  i don't understand can you rephrase that