whenever humans exhale carbon dioxide, plants take it in and use it to make a mixture of sunlight and water to create nutrients for itself. Once it creates the nutrients it releases oxygen which us humans use to breathe. This operation is called photosynthesis.
The answer to this is the remains and waste products of plants, animals and other living things organisms.
Different enzymes have specific active sites which can only catalyze one <span>substrate. Enzyme-substrate complexes are produced only when the substrate fits into the active site :)</span>
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