The difference between prophase I and prophase II is that crossing over between chromosomes takes place only in prophase I, not on prophase II. Prophase II ends where metaphase II begins. Prophase II: Meiosis II is initiated immediately after cytokinesis, usually. Spindle fibers grow outward from the centrosomes. with each parental cell giving rise to two daughter cells each time they. Metaphase II: The paired chromosomes line up. The centrosomes replicate and move towards the opposite poles. During prophase I and metaphase I of meiosis, a chromosome consists of a tetrad (4 chromatids or 4 DNA molecules) and is reduced to two chromatids (2 DNA. Meiosis II Prophase II: It is visibly obvious that replication has not occurred. If interkinesis takes place, the nuclear envelope and the nucleolus disintegrate during prophase II. Explanation: During prophase I homologous chromosomes will line up with one. Prophase II is the phase that follows after meiosis I, or after interkinesis if present. It consists of 4 sub-phases: Prophase II, Metaphase II, Anaphase II, Telaphase II. Each of these phases is designated as I or II depending where it occurs, i.e. M Phase: M phase is when mitosis actually begins to take place. These are prophase, metaphase, anaphase and telophase. That is because the parent cell undergoes two meiotic divisions called first meiotic division ( meiosis I) and second meiotic division ( meiosis II). During Prophase II, nuclear envelopes (if they formed during Telophase I). The resulting cells following meiosis contain half of the number of the chromosomes in the parent cell. Organisms with more than two sets of chromosomes are termed polyploid. The nuclear membrane also starts disappearing. Each chromosome at this stage has two chromatids that lie side by side and held together by centromere. Meiosis is a reproductive cell division since it gives rise to gametes. The genetic structures in cells composed of condensed DNA ,which contain the genetic code for an organism. The chromatin network begins to coil and each chromosome becomes distinct as long thread like structure. Spindle fibers move homologous chromosomes to opposite sides. The first stage in meiosis II highlighted by the disintegration of nucleolus and nuclear envelope, the shortening and thickening of the chromatids, and the replication and movement of centrosomes to polar regions Homologous chromosomes pair up and form tetrad.
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