What are chromosomes? Explain how in sexually reproducing organisms,the number of chromosomes in the progeny is maintained?

(N/A) Chromosomes are thread-like structures composed of $DNA$ and proteins,found within the nucleus of a cell.
In sexually reproducing organisms,the process of meiosis occurs during gamete formation. This process reduces the number of chromosomes to half $(n)$ in the gametes compared to the parent cell $(2n)$.
When fertilization occurs,the male gamete $(n)$ and the female gamete $(n)$ fuse to form a zygote $(2n)$. This fusion restores the original diploid number of chromosomes in the progeny,ensuring the stability of the species across generations.