The virus may have not developed fully the first time.
A classification systemwhere entries are arranged based on some hierarchical structure. filesystem, filing system. asystem of classifying into files (usually arranged alphabetically) grouping, pigeonholing. a systemfor classifying things into groups.
I believe mutation will make a population have more genetic variation. Genetic variation describes naturally occurring genetic differences among individuals of the same species. It is the difference in DNA sequences between individuals within a population. Variation permits flexibility and survival of a population in the face of changing environmental circumstances. It is considered an advantage, as it is a form of preparation for the unexpected.
The answer is A. <span>Solar energy is a renewable resource because it can't be used up, but oil is a nonrenewable resource because it will eventually run out.</span>
The cell cycle is a four-stage process in which the cell increases in size (gap 1, or G1, stage), copies its DNA (synthesis, or S, stage), prepares to divide (gap 2, or G2, stage), and divides (mitosis, or M, stage). The stages G1, S, and G2 make up interphase, which accounts for the span between cell divisions.
