Why can enzymes be used over and over again

Because enzymes are not consumed in the reactions they catalyze and can be used over and over again, only a very small quantity of an enzyme is needed to catalyze a reaction. A typical enzyme molecule can convert 1,000 substrate molecules per second.

Enzymes are biological catalysts. They catalyse biochemical reactions. They increase the rate of reaction. They do not chemically react or get utilised in the reaction so enzymes can be used over and over again.

the overall balanced equation

6co2 + 6h2o > c6h12o6 + 6o2

sunlight energy

where: co2 = carbon dioxide

h2o = water

light energy is required

c6h12o6 = glucose

o2 = oxygen

compost can be added to topsoil as a:

pesticide