What is the mechanism of attachment of the spindle fiber to the centromere of the chromosome during division?
A class protein complex call kinetochores allows microtubules of the spindle to attached to the chromosomes. The microtubules then pulled the chromosomes apart. Another complex call cohesin binds the sister chromosomes together. Then tension generated by the microtubules trying to pull the chromosomes apart and the cohesin trying to keep the chromosomes together help the cell ensure that all the chromosomes have the attached. When all the kinetochores are attached, the cell dissolves the cohesion which allows the chromosomes to pull apart. I don’t think in meiosis of an animal with non-homologous chromosomes (i.e. mules) that the chromosomes line up properly. Which I assume is one of the many reasons that animals like that are sterile.
