* Gametes: Fertilization involves the fusion of two specialized sex cells called gametes. Gametes are haploid, meaning they contain only half the number of chromosomes found in a normal body cell. For humans, this means each gamete (sperm and egg) has 23 chromosomes.
* Zygote: When a sperm and egg fuse, they form a single cell called a zygote. The zygote now has a complete set of chromosomes (23 from the sperm + 23 from the egg = 46 total).
* Diploid: The zygote is diploid, meaning it has two sets of chromosomes, one from each parent. This diploid state is maintained in all the cells that arise from the zygote through cell division, creating a new individual with a unique combination of genetic material from both parents.
In summary:
1. Haploid gametes (sperm + egg) fuse --> Diploid zygote is formed.
2. Zygote undergoes cell division, maintaining the diploid state in all new cells --> A diploid organism develops.
Fertilization is the crucial step in the sexual reproduction cycle that restores the diploid state, ensuring the continuation of a species with the full set of chromosomes necessary for its development and function.
