kromatidákra

Kromatidákra, also known as chromatids, are identical copies of a chromosome that are joined together at a region called the centromere. They are formed during the process of DNA replication, where each chromosome is duplicated to produce two sister chromatids. This duplication ensures that each new cell formed during cell division receives a complete set of genetic material.

Chromatids are held together by a structure called the cohesin complex, which is essential for proper chromosome segregation during cell division. The cohesin complex is released at specific points in the cell cycle, allowing the sister chromatids to separate and move to opposite poles of the cell during mitosis or meiosis.

During mitosis, the sister chromatids are pulled apart by the spindle fibers of the mitotic apparatus, and each chromatid is packaged into a new nucleus as a separate chromosome. In meiosis, the sister chromatids separate during the second meiotic division, resulting in the formation of haploid gametes.

The study of chromatids is crucial for understanding various genetic disorders and diseases, as abnormalities in chromosome structure and segregation can lead to genetic mutations and cellular dysfunction. Techniques such as fluorescence in situ hybridization (FISH) and chromosome painting are used to visualize and analyze chromatids in research and clinical settings.