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reticulum, nucleolus and the nuclear envelope., microscope, do not show golgi complexes, endoplasmic, Cells at the end of prophase, when viewed under the, s seen in haploid then, is the stage at which morphology of chromosomes is, lls in this sta, to exhibit divisi, casionally,, ury or cell des, Cri CYCLE AND CELL DIVISION, 165, as ne, death, enter an inacth, aless called on t, 10.2.2 Metaphase, amplete disintegration of the nuclear envelope marks, The cort of the second phase of mitosis, hence the, in the diploids, ere haploid cells, st this, the, loid cells. From, as in plants (Cha, hroniosomes are spread through the cytoplasm of the cell., Pr this stage, condensation of chromosomes is, Darhey can be observed clearly under the microscope. This, plan, Early Prophase, or chnomosonmes is, most easily studied. At this stage, metaphase chromosome, is made up of two sister chromatids, which are held together, by the centromere (Figure 10.2 b). Small disc-shaped, structures at the surface of the centromeres are called, kinetochores. These structures serve as the sites of attachment, of spindle fibres (formed by the spindle fibres) to the, chromosomes that are moved into position at the centre of, ss and very cle the cell. Hence, the metaphase is characterised by all the, chromosomes coming to lie at the equator with one chromatid, of each chromosome connected by its kinetochore to spindle, le, involving a, , Since the numb, ame, it is also ca, sis has been, di, it is very essenti, Late Prophase, (a), aryokinesis im, fibres from one pole and its sister chromatid connected by, its kinetochore to spindle fibres from the opposite pole (Figure, 10.2 b). The plane of alignment of the chromosomes at, metaphase is referred to as the metaphase plate. The key, features of metaphase are:, e Spindle fibres attach to kinetochores of, Transition to, chromosomes., O Chromosomes are moved to spindle equator and get, aligned along metaphase plate through spindle fibres, to both poles., Metaphase, mitosis follows, ases the new D, rophase is, al material, g the proces, some, which, ow begins to, rophase can, 10.2.3 Anaphase, At the onset of anaphase, each chromosome arranged at the, metaphase plate is split simultaneously and the two daughter, chromatids, now referred to as daughter chromosomes of, the future daughter nuclei, begin their migration towards, the two opposite poles. As each chromosome moves away, Hom the equatorial plate, the centromere of each chromosome, remains directed towards the pole and hence at the leading, edge, with the arms of the chromosome trailing behind Figure 10.2 a and b: A diagrammatic, (Figure 10.2 c). Thus, anaphase stage is characterised by view of stages in mitosis, Metaphase, (b), compact mi, Composed of, uring interph, Sach centros, Dasters tog