Figure 22.5 The equatorial plane

3. Anaphase. The centromere of each chromosome divides into two (figure 22.6). And the two centromeres thus formed begin separating. They are carrying the chromatids of which they are a part. Chromatids move towards the opposite poles of the spindle, and they become U- like or V - like shapes. It is not certain know whether some force develops which repels the two centromeres of a pair, or the fibers of the spindle, which are attached to centromeres, pull apart the two chromatids of a pair.

Figure 22.6 Anaphase.

4. Telophase. The chromatids of chromosomes move further apart reaching the poles of the spindle where they become grouped together near each centriole. The chromatids are now called new or daughter chromosomes. The new chromosomes become increasingly less distinct and they begin to uncoil (figure 22.7).

a nuclear membrane forms around each group of chromosomes to form two nuclei. A nucleolus is re-formed in each nucleus. The spindle and asters become indistinct and finally disappear, but the centriole persists. The new chromosomes become invisible and assume the interphase condition.

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