Why do we only have fossils of a fraction of the things that have existed on earth?

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes

Everything that surrounds a particular organism

5. what might happen if you were to remove all light from the setup after the discs have all become buoyant? describe what you would see. explain why this would occur with relation to cellular processes like respiration. [referring to an ap biology lab in which spinach discs are placed in a sodium bicarbonate solution and exposed to light.]