The chromosome number is reduced from the diploid to the haploid. The chromosome number remains constant at the end of mitosis. It is often simultaneous after second division to result in four new cells. Cytokinesis often does not occur after the first or reduction division. Cytokinesis follows every mitosis.It produces two new cells. Spindle fibers do not disappear completely in telophase I. Spindle fibers disappear completely in telophase. Dissimilar chromosomes move towards the opposite poles both in anaphase I and II. Similar chromosomes move towards the opposite poles in anaphase. Chromosomes are double stranded in anaphase I, but single stranded in anaphase II. Anaphase chromosomes are single stranded. Short chromosomes separate early, separation of long chromosome is delayed. The chromosomes separates simultaneously during anaphase. Centromeres divide only during anaphase II. There is no centromeric division during anaphase I. Division of the centromeres take place during anaphase. The chromosomes of daughter cells usually contain a mixture of maternal and paternal genes. The genetic constitution of the daughter cells differs from that of the parent cell. Two chromatids of a chromosome (Progeny cells) are often genetically different due to crossing over. The genetic constitution of the daughter cells is identical to that of the parent cells. Two chromatids of a chromosome (Progeny cells) are genetically similar. The metaphase plate is made up of paired chromosome pairs. The metaphase plate is made up of chromosome pairs. In metaphase I the centromeres are lined up in two planes which are parallel to one other. Chiasmata are absent.Ĭhiasmata or visible connections between homologous chromosomes of bivalents are observed during diplotene, diakinesis (prophase I) and metaphase I In the metaphase plate all the centromeres line up in same plate. Crossing over is absent.Ĭrossing over or exchange of similar segments between nonsister chromatids of homologous chromosomes usually take place during pachytene stage. Synapsed homologous chromosome develop a synaptonemal complex. No bouquet stage is recorded.Ĭhromosomes of animals and some plants show covergence towards one side during early prophase I. Chromosomes are already duplicated at the beginning of prophase When prophase I commences the chromosomes appear single, (although DNA replication has taken place in interphase I). The arms of the chromatids are separated widely in prophase II. The arms of the prophase chromatids are close to one another. Chromatids of two homologous chromosomes exchange segments during crossing over. The two chromatids of a chromosome do not exchange segments during prophase. Synapsis of homologous chromosomes takesplace during prophase. There are two cell divisions but the chromosomes divide only once. The cell divides only once and the chromosomes also divide only once. Prophase is complicated and divided into leptotene, zygotene, pachytene, diplotene, and diakinesis. Prophase is comparatively longer and may take days. The DNA replicates once for two cell divisions The duration of prophase is short, usually of a few hours. DNA replication takes place during interphase I but not interphase II The DNA replicates once for one cell division. DNA replication takes place during interphase I. Interphase occurs prior to each division. There are two cell divisions, the first and the second meiotic divisions. Occurs only in sexually reproducing organisms. Occurs in both sexually as well as asexually reproducing organisms. Take place in the somatic cells of the body.
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