Why is it possible for different microorganisms to extract energy not only from carbohydrates and other biological molecules but from a large variety of substances?

The answer is true for your question.

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.