The no of chromosomes of a organism of each generation is maintained due to the meiosis.
Step-by-step explanation:
The meosis is a kind of reductive division for the higher organisms and for the higher organism it is mitosis. The mitosis is the phase where the organism reproduce asexually, in this phase the two resulting daughter cells always contains the same no of chromosomes as the parent cell from which they derive.
The role of chromosomes is to maintain the each cell division is constant. It help us to enable us to grow and self maintenance of the body.