Final answer:
Prometaphase is a stage of mitosis where important events, such as the attachment of spindle fiber microtubules to kinetochore proteins, occur. In this stage, the nuclear membrane breaks down and microtubules pull homologous pairs of chromosomes apart. At the end of prometaphase, each tetrad is attached to microtubules from both poles.
Step-by-step explanation:
Prometaphase is a stage of mitosis in which several important events occur. One of these events is the attachment of the spindle fiber microtubules to the kinetochore proteins at the centromeres. The kinetochore proteins are multiprotein complexes that bind the centromeres of a chromosome to the microtubules of the mitotic spindle. This attachment allows the microtubules to pull the homologous pair of chromosomes apart.
In prometaphase, the nuclear membrane has also completely broken down, allowing the microtubules to access the chromosomes. At the end of prometaphase, each tetrad is attached to microtubules from both poles of the cell, with one homologous chromosome facing each pole.