What's a chemical reaction?

process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction

by the way it is not biology subject

hlo krutika

can I talk to u in comment section

a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

helicase, i think thats it

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).