Diploid cells include all animal cells, including those of humans. They are also found in the cells of flowering plants, gymnosperms and in one of the two generations of algae and lower plants. Diploid cells are cells containing chromosomes, which exist in pairs.
Diploid cells confer an advantage to the organism. If there is a genetic mutation or any gene damage, the functional chromosome may be used instead. Diploid chromosomes also give an organism an advantage in evolution. If one chromosome is not suited well for the environment, the other may be able to compensate and allow the organism to thrive.