What is a scientific conclusion based on much supporting evidence

During the day, plants produce by splitting water molecules in the light-dependent reactions of photosynthesis. at the same time, plants use cellular respiration to produce some of the needed by the light-independent reactions to make sugars. during the night, plants produce because takes place.

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

Crossing over is a method of (blank)?