Simple diffusion: requires energy utilizes proteins to move molecules across a membrane moves molecules against a concentration gradient cannot occur without a membrane present does not require energy

Which of the following is not a main characteristic that scientists focus on when determining which kingdom an organism belongs to

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .

The color of the fur is the genotypephenotype.the genetic combination of alleles that determine the fur color is called the genotypephenotype.