The fusion of kinetochores of sister chromatids is relaxed in meiosis-II and again a separation would require 23 fibres. In meiosis-I there is a tetrad which has 2 kinetochore pairs but the ones in sister chromatids behave as a single unit. In a normal mitotic metaphase there are 2n kinetochore pairs, and as you rightly calculated, there will be 96 K-fibres. I cant surely say that there is exactly one K-fibre per kinetochore but as per its definition and from the microscopic images you can conclude that there is one per kinetochore. The fibres attached to kinetochores are called K-fibres and the others are called polar fibres. The neurons do not contain the centriole, hence are not capable of division.The number of spindle fibres is actually more than total number of kinetochore pairs. It helps in equal segregation any defect in it causes chromosomal defects. 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. Spindle fibers form a protein structure that divides the genetic material in a cell. The microtubules extend from centrioles to every direction possible, forming a spindle. chromosomes condense and become visible spindle fibers emerge from the centrosomes Prometaphase is the. At the initial stages of karyokinesis, two centrioles (wheel-shaped) take positions at opposite sides of a cell, forming poles. Plant cells lack centrioles but can form a mitotic spindle. However, at the time of meiosis, the spindle fibers are said to be the meiotic spindle. Recent studies on plant mitosis show that plants utilize a variation of spindle self-organization. At the time of mitosis, these fibers are called the mitotic spindles. Chromosomes move toward the center of the cell (equatorial plate). They are absolutely imperative in equal division of the chromosomes between two daughter cells during nuclear division: mitosis or meiosis. For tissues composed of cells that can undergo mitosis, like the liver. Spindle fibers have their main role in dividing the genetic material of a cell. String - like fibers called microtubular spindle fibers form from the centrioles. 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. Hint: Spindle fibers are the protein structures which segregate the genetic material in a cell.
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