What might introduction of exotic species disrupt an ecosystem

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?

Moving down the ramp from 6 meters to

How secretion and excretion both are different? explain in simple language.