Ferns are simultaneously involved in promoting rock weathering, while preventing soil erosion. Explain how a single plant can perform both these functions, and how these functions are beneficial to its ecosystem.

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).

plato users:

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there was a variety of food available on island x, but there were only large seeds and nuts on island y.

can i pls have the choices?