Most of what we know about the lac operon of E. coli has come from genetic analysis of various mutants. In the following list are the genotypes of six strains of E. coli. For each strain, indicate whether the lacZ gene product (B-gal) will be expressed in the presence of lactose and whether it will be expressed in the absence of lactose. Explain your reasoning in each case. (A "plus" superscript indicates normal functioning part of operon or repressor gene, a "minus" indicates loss of function, the P region is where the RNA polymerase binds, "Oc" means "operator-constitutive" mutant which means that the operator is mutated such that the repressor can’t bind, and "Is" means "super-repressor" which binds the operator, but doesn’t bind lactose (so never dissociates from the operator).

slitherio is the original. its the best friend of all middle schoolers. the man you can count any time you have some free time. slitherio is the guy you hang with while you're in the computer lab suppose to be doing "research or whatever". slitherio isn't just a game but a friend.

wormaxio is just a fake trying to squeeze its way into the friend group. trying to pretend its cool and your best pal but how long has it really been there for you, really. it only wants you as friend to boost its social status. wormaxio is just annoying fake pleb. no offense

you and have a wonderful day

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).