Mayoz

Mayoz, or meiosis in biology, is a specialized form of cell division that reduces the chromosome number by half, producing four genetically unique haploid cells from a single diploid precursor. It is central to sexual reproduction and occurs in germ cells during gametogenesis. The process consists of two sequential divisions, meiosis I and meiosis II, preceded by a round of DNA replication during interphase.

In prophase I, homologous chromosomes pair in a process called synapsis, forming tetrads. Crossing over may occur, exchanging genetic material between homologs, contributing to genetic diversity. The nucleolus disappears, the spindle forms, and homologous pairs align at the metaphase plate during metaphase I. Anaphase I pulls apart homologous chromosomes, not sister chromatids, reducing the chromosome number in each daughter cell. Telophase I and cytokinesis typically result in two haploid cells, each with replicated chromosomes.

Meiosis II resembles mitosis. In prophase II, the chromosomes condense again; metaphase II, chromosomes align; anaphase II, sister chromatids separate; telophase II and cytokinesis split the cells, yielding a total of four haploid gametes with distinct genetic compositions.

Key features distinguishing meiosis from mitosis include homologous chromosome pairing, crossing over, and the random orientation of pairs leading to independent assortment. Errors such as nondisjunction can produce aneuploid gametes. Mayoz is essential for maintaining species chromosome number across generations and for creating genetic variation in offspring.