Answer:
This is known as Population.
Explanation:
A population is made up of organisms of the same kind living together in the same habitat. Characteristics of a population include the population size, frequency, density, percentage cover and distribution.
Factors that dominantly affect a population comes up especially in size and distribution. These factors include; migration of organisms to other habitats, invasion or colonization by new species, increase or decrease in birth and death rates etc
Meiosis involves crossing over where chromosomes exchange genetic segments, resulting in different sets of chromosomes. Each time an egg or sperm created, it is different due to this recombination. Mitosis on the other hand is non-sex cells replicating exact copies of themselves which lead to no genetic variation as they aren't involved in producing offspring.