during mitosis what happens to the parent cell
Mitosis is the process in which a eukaryotic cell nucleus splits in two, followed by sectionalisation of the parent cell into 2 daughter cells. The word "mitosis" means "threads," and it refers to the threadlike advent of chromosomes as the cell prepares to divide. Early on microscopists were the showtime to discover these structures, and they also noted the appearance of a specialized network of microtubules during mitosis. These tubules, collectively known as the spindle, extend from structures chosen centrosomes — with one centrosome located at each of the opposite ends, or poles, of a cell. As mitosis progresses, the microtubules attach to the chromosomes, which have already duplicated their DNA and aligned across the center of the cell. The spindle tubules then shorten and movement toward the poles of the prison cell. As they motility, they pull the ane copy of each chromosome with them to opposite poles of the cell. This procedure ensures that each daughter cell will incorporate ane verbal re-create of the parent jail cell Dna.
What Are the Phases of Mitosis?
Mitosis consists of v morphologically distinct phases: prophase, prometaphase, metaphase, anaphase, and telophase. Each phase involves characteristic steps in the process of chromosome alignment and separation. One time mitosis is complete, the unabridged cell divides in ii past way of the process chosen cytokinesis (Figure i).
Figure one: Drawing of chromosomes during mitosis past Walther Flemming, circa 1880
This illustration is one of more than i hundred drawings from Flemming'due south \"Cell Substance, Nucleus, and Cell Division.\" Flemming repeatedly observed the different forms of chromosomes leading upwards to and during cytokinesis, the ultimate division of one cell into ii during the concluding phase of mitosis.
© 2001 Nature Publishing Group Paweletz, N. Walther Flemming: pioneer of mitosis research. Nature Reviews Molecular Prison cell Biology ii, 72 (2001). All rights reserved. 
What Happens during Prophase?
Prophase is the outset stage in mitosis, occurring later the conclusion of the Gii portion of interphase. During prophase, the parent cell chromosomes — which were duplicated during S phase — condense and become thousands of times more compact than they were during interphase. Because each duplicated chromosome consists of 2 identical sister chromatids joined at a indicate called the centromere, these structures now appear as X-shaped bodies when viewed nether a microscope. Several DNA binding proteins catalyze the condensation process, including cohesin and condensin. Cohesin forms rings that hold the sister chromatids together, whereas condensin forms rings that gyre the chromosomes into highly meaty forms.
The mitotic spindle as well begins to develop during prophase. As the cell's two centrosomes move toward opposite poles, microtubules gradually assemble between them, forming the network that volition later pull the duplicated chromosomes apart.
What Happens during Prometaphase?
When prophase is complete, the prison cell enters prometaphase — the 2d stage of mitosis. During prometaphase, phosphorylation of nuclear lamins by Thou-CDK causes the nuclear membrane to break downwardly into numerous small vesicles. As a issue, the spindle microtubules at present have direct access to the genetic material of the cell.
Each microtubule is highly dynamic, growing outward from the centrosome and collapsing backward as information technology tries to locate a chromosome. Somewhen, the microtubules find their targets and connect to each chromosome at its kinetochore, a circuitous of proteins positioned at the centromere. The actual number of microtubules that attach to a kinetochore varies between species, just at least one microtubule from each pole attaches to the kinetochore of each chromosome. A tug-of-war then ensues as the chromosomes move dorsum and forth toward the two poles.
What Happens during Metaphase and Anaphase?
As prometaphase ends and metaphase begins, the chromosomes align along the jail cell equator. Every chromosome has at least two microtubules extending from its kinetochore — with at to the lowest degree one microtubule connected to each pole. At this signal, the tension within the cell becomes balanced, and the chromosomes no longer motility back and forth. In add-on, the spindle is at present complete, and three groups of spindle microtubules are credible. Kinetochore microtubules attach the chromosomes to the spindle pole; interpolar microtubules extend from the spindle pole beyond the equator, virtually to the opposite spindle pole; and astral microtubules extend from the spindle pole to the cell membrane.
Metaphase leads to anaphase, during which each chromosome's sister chromatids separate and motility to opposite poles of the prison cell. Enzymatic breakdown of cohesin — which linked the sister chromatids together during prophase — causes this separation to occur. Upon separation, every chromatid becomes an contained chromosome. Meanwhile, changes in microtubule length provide the mechanism for chromosome movement. More specifically, in the first part of anaphase — sometimes chosen anaphase A — the kinetochore microtubules shorten and draw the chromosomes toward the spindle poles. And so, in the second part of anaphase — sometimes called anaphase B — the astral microtubules that are anchored to the cell membrane pull the poles further apart and the interpolar microtubules slide past each other, exerting additional pull on the chromosomes (Effigy 2).
Figure ii: Types of microtubules involved in mitosis
During mitosis, several types of microtubules are agile. The motor proteins associated with the interpolar microtubules bulldoze the associates of the spindle. Note the other types of microtubules involved in anchoring the spindle pole and pulling apart the sister chromatids.
What Happens during Telophase?
During telophase, the chromosomes arrive at the jail cell poles, the mitotic spindle disassembles, and the vesicles that contain fragments of the original nuclear membrane assemble around the ii sets of chromosomes. Phosphatases then dephosphorylate the lamins at each end of the prison cell. This dephosphorylation results in the formation of a new nuclear membrane effectually each group of chromosomes.
When Practise Cells Really Divide?
Cytokinesis is the physical process that finally splits the parent cell into 2 identical girl cells. During cytokinesis, the cell membrane pinches in at the cell equator, forming a cleft called the cleavage furrow. The position of the furrow depends on the position of the astral and interpolar microtubules during anaphase.
The cleavage furrow forms because of the activity of a contractile ring of overlapping actin and myosin filaments. As the actin and myosin filaments move by each other, the contractile ring becomes smaller, akin to pulling a drawstring at the top of a purse. When the ring reaches its smallest point, the cleavage furrow completely bisects the jail cell at its middle, resulting in two separate daughter cells of equal size (Figure 3).
Figure 3: Mitosis: Overview of major phases
The major stages of mitosis are prophase (peak row), metaphase and anaphase (middle row), and telophase (bottom row).
Conclusion
Mitosis is the process of nuclear segmentation, which occurs merely prior to cell sectionalization, or cytokinesis. During this multistep process, cell chromosomes condense and the spindle assembles. The duplicated chromosomes and so attach to the spindle, align at the cell equator, and move apart as the spindle microtubules retreat toward opposite poles of the cell. Each prepare of chromosomes is then surrounded past a nuclear membrane, and the parent cell splits into two complete daughter cells.
Source: https://www.nature.com/scitable/topicpage/mitosis-14046258/
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