![]() At the end of anaphase, each pole contains a complete compilation of chromosomes. Location and Checks and Balances Kinetochores form in the central region, or centromere, of a duplicated chromosome. These fibers work together to separate chromosomes during cell division. In preparation for telophase, the two cell poles also move further apart during the course of anaphase. Kinetochore fibers extend from the kinetochore region and attach chromosomes to microtubule spindle polar fibers. ![]() The daughter chromosomes migrate centromere first and the kinetochore fibers become shorter as the chromosomes near a pole..Through the spindle apparatus, the daughter chromosomes move to the poles at opposite ends of the cell..They are referred to as daughter chromosomes. Once the paired sister chromatids separate from one another, each is considered a "full" chromosome.The paired centromeres in each distinct chromosome begin to move apart..During anaphase, the following key changes occur: Spindle fibers not connected to chromatids lengthen and elongate the cell. In anaphase, the paired chromosomes ( sister chromatids) separate and begin moving to opposite ends (poles) of the cell. Q2 What are spindle fibers made of Spindle fiber is most abundantly composed of the microtubule, which is a polymer of and -tubulin dimer. They help in the movement of chromosomes during both mitosis and meiosis. The chromosomes begin to migrate toward the cell center. Spindle fiber is a network of filaments that are formed during the cell division process.The kinetochore fibers "interact" with the spindle polar fibers connecting the kinetochores to the polar fibers.Kinetochores, which are specialized regions in the centromeres of chromosomes, attach to a type of microtubule called kinetochore fibers.Polar fibers, which are microtubules that make up the spindle fibers, reach from each cell pole to the cell's equator.The two pairs of centrioles (formed from the replication of one pair in Interphase) move away from one another toward opposite ends of the cell due to the lengthening of the microtubules that form between them.The mitotic spindle, composed of microtubules and proteins, forms in the cytoplasm.Chromatin fibers become coiled into chromosomes, with each chromosome having two chromatids joined at a centromere.During prophase, a number of important changes occur: Prophase (versus interphase) is the first true step of the mitotic process. There are several types of spindle inhibiting drugs. The nuclear envelope breaks down and spindles form at opposite poles of the cell. Spindle inhibitors affect the creation of the spindle fiber mechanism, stopping cell division. In prophase, the chromatin condenses into discrete chromosomes.
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