Biology · Cell Cycle
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During meiosis, the homologous chromosomes come together and form pairs, this process is called:
- A
Linkage
- B
Synapsis
- C
Pairing
- D
Crossing over
During meiosis, homologous chromosomes come together and form pairs through a process called "synapsis." The synapsis involves the alignment of homologous chromosomes side by side, allowing for the exchange of genetic material between non-sister chromatids during "crossing over." This genetic recombination during crossing over plays a critical role in creating genetic diversity in the gametes, which is essential for sexual reproduction. The other options, "linkage" and "pairing," are not specific to the process of homologous chromosome pairing during meiosis.
Linkage is a term used to describe the tendency of genes located on the same chromosome to be inherited together as a unit. Genes that are close to each other on the same chromosome have a higher chance of being inherited together during the process of meiosis, and this phenomenon is known as genetic linkage. However, during meiosis, linkage does not involve the physical pairing of homologous chromosomes.
Synapsis is the correct option. During meiosis, specifically during the first stage of meiosis (prophase I), homologous chromosomes come together and physically pair up. This pairing process is called "synapsis," and it involves the formation of a protein structure known as the synaptonemal complex. The synaptonemal complex helps to align the homologous chromosomes side by side, allowing for the exchange of genetic material between non-sister chromatids through a process called crossing over.
"Pairing" is a general term that can refer to various processes in biology. In the context of the given question, "pairing" could be considered a vague or general term for describing the coming together of homologous chromosomes during meiosis. The more specific and accurate term for this process is "synapsis," as explained above.
Crossing over is a genetic phenomenon that occurs during meiosis, specifically during prophase I. It is the exchange of genetic material between non-sister chromatids of homologous chromosomes that are physically paired up during synapsis. Crossing over leads to genetic recombination, where new combinations of alleles are formed on the chromatids, increasing genetic diversity in the gametes produced during meiosis.
Tagged under Biology · Cell Cycle · 2020