ANATOMY

Detailed explanation-1: -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-2: -At the beginning of mitosis, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down, resulting in the release of most of the contents of the nucleus into the cytoplasm.

Detailed explanation-3: -Phase 1 – Prophase: In this phase the nuclear membrane begins to break down and the DNA forms structures called chromosomes. The four stages of mitosis (the cell at the top has not started mitosis) lead to two daughter cells. A little after telophase, the cytoplasm splits and a new cell membrane forms.

Detailed explanation-4: -During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. The chromatin coils and becomes increasingly compact, resulting in the formation of visible chromosomes.

Detailed explanation-5: -During prophase the centrosome divides into two parts and a centriole pair migrates to each end or pole on the outside of the nuclear membrane or envelope. At this point microtubules are produced at the outer edge of the pericentriolar material and grow out in a radial form.