PATHOLOGY

Detailed explanation-1: -During prophase, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down.

Detailed explanation-2: -In order for these processes to occur, the nuclear membrane must be dissolved during the earliest mitotic phase: prophase. During prophase, DNA condenses into chromosomes, the nuclear membrane dissolves, and the chromosomes enter the cytoplasm.

Detailed explanation-3: -After prophase is complete, the cell enters prometaphase. During prometaphase, the nuclear membrane disintegrates and the mitotic spindle gains access to the chromosomes. During this phase, a protein structure called the kinetochore is associated with the centromere on each sister chromatid.