Which process occurs in all sexually reproducing eukaryotes?

Meiosis is a fundamental process that occurs in all sexually reproducing eukaryotes. This specialized form of cell division is essential for generating gametes, which are the reproductive cells necessary for sexual reproduction. In eukaryotes, meiosis results in the halving of the chromosome number, transforming diploid cells into haploid cells, thereby maintaining the chromosome number across generations when fertilization occurs.

The significance of meiosis lies in its ability to introduce genetic diversity through processes such as crossing over and independent assortment during the formation of gametes. This genetic variation is crucial for evolution and adaptation in changing environments.

In contrast, while mitosis is also a process of cell division, it is primarily involved in growth and repair and does not contribute to the production of genetically diverse gametes. Binary fission is a form of asexual reproduction commonly found in prokaryotes, and cloning refers to the process of producing genetically identical copies of an organism, which does not involve the mixing of genetic material as seen in sexual reproduction.