The centrosomes have replicated and are moving toward the poles.Īgain, the chromosomes are not yet attached to the spindle apparatus, which is growing outward from the centrosomes. If there was an interkinesis, then the nuclear envelopes begin to break down again during this stage. During this stage of spermatogenesis, the cells are called secondary spermatocytes, or during oogenesis, secondary oocytes. As in prophase I, the chromosomes are condensed. They are called prophase 2, prometaphase 2, metaphase 2, anaphase 2, and telophase 2 to distinguish them from the first round of meiotic division. The mitotic prophase and prophase II are quite comparable. It explains how mitosis and meiosis vary from one another. Prophase 2 - During this stage nuclear envelopes dissolve and. 1) Two successive cell division without DNA replication 2) Pairing of homologous chromosomes during prophase I followed by formation of chaismata and crossing. With the pairing of homologous chromosomes and the exchange of genetic material, prophase I is highly complicated. Meiosis 2 is pretty much like mitosis with the exception that no genetic material is copied. Prophase II, the first step of meiosis II, begins with the two daughter cells produced by the first meiotic division (see figure right). The prophase, which occurs in two phases, prophase I and prophase II, is what makes the process lengthier. They line up at the midway point between the two poles of the cell to form the metaphase plate. Prophase II Note: Meiosis II is very similar to mitosis, except that during meiosis II only one member of each chromosome homolog pair is present, whereas in mitosis both are (it will help you remember this if you pronounce mitosis - only in your own mind! - as "my- TWO-sis"). Prophase II of meiosis forms the tetrads.
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