homologous chromosome

biology

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June 29, 2026

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Homologous chromosomes are pairs of chromosomes that have the same genes in the same order, though the specific versions of those genes (alleles) may differ. One chromosome in each pair is inherited from each parent. These homologous chromosomes are crucial for sexual reproduction and are organized into pairs within the cell nucleus.1234

During meiosis, a specialized type of cell division that produces gametes (sex cells), homologous chromosomes pair up and can exchange genetic material through a process called crossing over. This exchange shuffles genes, creating genetic diversity in the resulting gametes. After crossing over, the homologous chromosomes separate, and each gamete receives only one chromosome from each pair, thus halving the chromosome number. When fertilization occurs, the fusion of two gametes restores the diploid number of chromosomes in the offspring.1546

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evolution
Chromosomal mutations
…of a pair are called homologous chromosomes. Each cell of an organism and all individuals of the same species have, as a rule, the same number of chromosomes. The reproductive cells (gametes) are an exception; they have only half as many chromosomes as the body (somatic) cells. But the number,…
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…of a pair are called homologous chromosomes. Each cell of an organism and all individuals of the same species have, as a rule, the same number of chromosomes. The reproductive cells (gametes) are an exception; they have only half as many chromosomes as the body (somatic) cells. But the number,…
Read More