Chromatin condensation begins during prophase (2) and chromosomes become visible. Chromosomes remain condensed throughout the various stages of mitosis (2-5). … However, when eukaryotic cells are not dividing — a stage called interphase — the chromatin within their chromosomes is less tightly packed.
Does chromatin condense into chromosomes in meiosis?
Meiosis I, the first meiotic division, begins with prophase I. During prophase I, the complex of DNA and protein known as chromatin condenses to form chromosomes. The pairs of replicated chromosomes are known as sister chromatids, and they remain joined at a central point called the centromere.
Do chromosomes condense in mitosis or meiosis?
A unique feature of the nucleus is that it disassembles and re-forms each time most cells divide. At the beginning of mitosis, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down, resulting in the release of most of the contents of the nucleus into the cytoplasm.
Why are chromosomes visible during mitosis?
Chromosomes become visible during mitosis because they condense themselves to thick, visible strands. Regularly, they are more spread out as thin strands and therefore invisible to the eye even with a microscope.
What phases of mitosis are chromosomes visible?
Mitosis has four sequential stages: prophase, metaphase, anaphase, and telophase. In prophase, each chromosome becomes condensed and more visible, and there is the breakdown of the nuclear membrane and appearance of spindle fibers. In the next phase, metaphase, the chromosomes line up along the metaphasic plate.
What happens when a chromosome condenses?
Nuclear Changes in Prophase
Chromosome condensation, the landmark event at the onset of prophase, often begins in isolated patches of chromatin at the nuclear periphery. Later, chromosome condense into two threads termed sister chromatids that are closely paired along their entire lengths.
Why is chromosome condensing needed for cell division?
Chromosome condensation is mediated by the condensin complex, among other proteins, and is necessary to prevent chromosomes from being entangled during chromosome segregation.