![]() Spindle fibers are essential for both types of nuclear division that is- meiosis and mitosis. Now, during anaphase of the cell cycle, the chromosomes separate and move to opposite sides. The chromosomes are attached to the fibres and divide. At the time of division, particularly at metaphase, these tubules pull and align the chromosome at the equator of the cell, which is also known as the metaphasic plate. Some of them attach the poles to the kinetochores around the centromere. ![]() The microtubules extend from centrioles to every direction possible, forming a spindle. At the initial stages of karyokinesis, two centrioles (wheel-shaped) take positions at opposite sides of a cell, forming poles. However, at the time of meiosis, the spindle fibers are said to be the meiotic spindle. At the time of mitosis, these fibers are called the mitotic spindles. They are absolutely imperative in equal division of the chromosomes between two daughter cells during nuclear division: mitosis or meiosis. Spindle fibers have their main role in dividing the genetic material of a cell. Spindle formation and division in eukaryotes. Plant cells lack centrioles but can form a mitotic spindle from the centrosome area. Recent studies on plant mitosis show that plants utilize a variation of "spindle self-organization". The plants have evolved new mechanisms to carry out chromosome segregation. The plant cells entirely lack centrosomes which have a major role in spindle formation. Chromosomes, spindle fibers and kinetochores all have significant roles during mitosis. In all eukaryotic organisms, the formation of a bipolar spindle is obligatory for the proper segregation of chromosomes to the daughter cells. They later function in pulling apart the sister chromatids to the opposite poles so that the two new daughter cells that have formed will each possess one set of chromosomes. The replicated chromosomes link at their centromeres with these fibers. The nucleus reforms and the cell divides.Hint: Spindle fibers are the protein structures which segregate the genetic material in a cell. Cohesin proteins break down and the sister chromatids separate. Sister chromatids line up at the metaphase plate. The kinetochore becomes attached to the mitotic spindle.The nucleus reforms and the cell divides. The kinetochore breaks down and the sister chromatids separate. The kinetochore becomes attached to the cohesin proteins. ![]() ![]() The kinetochore becomes attached to the mitotic spindle. Sister chromatids line up at the metaphase plate.Which of the following is the correct order of events in mitosis? Answer c occurs during telophase, which happens after anaphase. During anaphase, the cohesin proteins binding the sister chromatids together also break down, and the non-kinetochore spindle fibers lengthen, elongating the cell.Īnswer a occurs during metaphase, which happens before anaphase. This is one of the events that occur during anaphase.
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