Detailed Summary of Metaphase
In the metaphase stage of mitosis, the nuclear envelope completely disintegrates, allowing chromosomes to spread throughout the cytoplasm. By this stage, the condensation of chromosomes is fully complete, enabling them to be observed distinctly under a microscope. Each chromosome consists of two sister chromatids, joined at the centromere.
Critical structures known as kinetochores, located at the centromeres, play an essential role as attachment sites for spindle fibers. The spindle fibers then align all chromosomes at the spindle equator or metaphase plate, ensuring accurate separation of chromatids during subsequent anaphase. During this process, each chromatid is attached to spindle fibers from opposite poles, guaranteeing that one copy of each chromosome is pulled toward each daughter cell. Key characteristics of this phase include:
- Spindle fibers attach to kinetochores of chromosomes.
- Chromosomes align along the metaphase plate, preparing for division.
Understanding metaphase is crucial as it ensures the accurate segregation of genetic material, which is fundamental for maintaining the genetic stability of daughter cells.