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what is the process occurring during pro-phase?

The events that occur during prophase of mitosis also occur during prophase I of meiosis. The chromosomes coil up, the nuclear membrane begins to disintegrate, and the centrosomes begin moving apart.

Synapsis (joining) of homologous chromosomes produces tetrads (also called bivalents).

The two chromosomes may exchange fragments by a process called crossing over.

When the chromosomes partially separate in late prophase, the areas where crossing over occurred remain attached and are referred to as Chiasmata (sing. chiasma). They hold the chromosomes together until they separate during anaphase.

Crossing over between homologous chromosomes is likely to occur at several different points, resulting in chromosomes that are mixtures of the original two chromosomes.

One kinetochore forms on each chromosome instead of on each chromatid as in mitosis.

The spindle fibers attach to the chromosomes and begin to move them to the center of the cell as they do in mitosis.

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