AP BIOLOGY

Detailed explanation-1: -The first and longest phase of mitosis is prophase. During prophase, chromatin condenses into chromosomes, and the nuclear envelope (the membrane surrounding the nucleus) breaks down. In animal cells, the centrioles near the nucleus begin to separate and move to opposite poles of the cell.

Detailed explanation-2: -During prophase, the nucleus disappears, spindle fibers form, and DNA condenses into chromosomes (sister chromatids).

Detailed explanation-3: -During prophase, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down.

Detailed explanation-4: -At the beginning of the first mitotic stage, prophase, the thread-like doubled chromosomes contract and become visible. The two centrioles move to opposite sides of the nucleus. At the same time, the nuclear membrane begins to break down.

Detailed explanation-5: -Mitosis is the process of cell division, and is separated into four stages. During prophase, the chromosomes condense and the nuclear envelope dissolves. During metaphase, the chromosomes align at the center of the cell. During anaphase, the sister chromatids are separated and pulled to opposite ends of the cell.