what is mitosis described various stages of mitosis
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What is mitosis? -
Mitosis is the phase of the cell cycle where chromosomes in the nucleus are evenly divided between two cells. When the cell division process is complete, two daughter cells with identical genetic material are produced.
★nterface -
Before a dividing cell enters mitosis, it undergoes a period of growth called interphase. Some 90 percent of a cell's time in the normal cellular cycle may be spent in interphase.
G1 phase: The period prior to the synthesis of DNA. In this phase, the cell increases in mass in preparation for cell division. Note that the G in G1 represents gap and the 1 represents first, so the G1 phase is the first gap phase.
S phase: The period during which DNA is synthesized. In most cells, there is a narrow window of time during which DNA is synthesized. Note that the S represents synthesis.
G2 phase: The period after DNA synthesis has occurred but prior to the start of prophase. The cell synthesizes proteins and continues to increase in size. Note that the G in G2 represents gap and the 2 represents second, so the G2 phase is the second gap phase.
In the latter part of interphase, the cell still has nucleoli present.
The nucleus is bounded by a nuclear envelope and the cell's chromosomes have duplicated but are in the form of chromatin.
In animal cells, two pair of centriolesformed from the replication of one pair are located outside of the nucleus.
★IN LATE PROPHASE
The nuclear envelope breaks up.
Polar fibers, which are microtubules that make up the spindle fibers, reach from each cell pole to the cell's equator.
Kinetochores, which are specialized regions in the centromeres of chromosomes, attach to a type of microtubule called kinetochore fibers.
The kinetochore fibers "interact" with the spindle polar fibers connecting the kinetochores to the polar fibers.
The chromosomes begin to migrate toward the cell center.
★Anaphase -
In anaphase, the paired chromosomes(sister chromatids) separate and begin moving to opposite ends (poles) of the cell. Spindle fibers not connected to chromatids lengthen and elongate the cell. At the end of anaphase, each pole contains a complete compilation of chromosomes.
CHANGES THAT OCCUR IN ANAPHASE
The paired centromeres in each distinct chromosome begin to move apart.
Once the paired sister chromatids separate from one another, each is considered a "full" chromosome. They are referred to as daughter chromosomes.
Through the spindle apparatus, the daughter chromosomes move to the poles at opposite ends of the cell.
The daughter chromosomes migrate centromere first and the kinetochorefibers become shorter as the chromosomes near a pole.
In preparation for telophase, the two cell poles also move further apart during the course of anaphase. At the end of anaphase, each pole contains a complete compilation of chromosomes.
Cytokinesis (the division of the original cell's cytoplasm) begins and continues through telophase.
Telophase -
CHANGES THAT OCCUR IN TELOPHASE
The polar fibers continue to lengthen.
Nuclei (plural form of nucleus) begin to form at opposite poles.
The nuclear envelopes of these nuclei are formed from remnant pieces of the parent cell's nuclear envelope and from pieces of the endomembrane system.
Nucleoli (plural form of nucleolus) also reappear.
Chromatin fibers of chromosomes uncoil.
After these changes, telophase/mitosis is largely complete and the genetic contents of one cell have been divided equally into two.
CYTOKINESIS
Cytokinesis is the division of the cell's cytoplasm. It begins prior to the end of mitosis in anaphase and completes shortly after telophase/mitosis. At the end of cytokinesis, two genetically identical daughter cells are produced
What is mitosis? -
Mitosis is the phase of the cell cycle where chromosomes in the nucleus are evenly divided between two cells. When the cell division process is complete, two daughter cells with identical genetic material are produced.
★nterface -
Before a dividing cell enters mitosis, it undergoes a period of growth called interphase. Some 90 percent of a cell's time in the normal cellular cycle may be spent in interphase.
G1 phase: The period prior to the synthesis of DNA. In this phase, the cell increases in mass in preparation for cell division. Note that the G in G1 represents gap and the 1 represents first, so the G1 phase is the first gap phase.
S phase: The period during which DNA is synthesized. In most cells, there is a narrow window of time during which DNA is synthesized. Note that the S represents synthesis.
G2 phase: The period after DNA synthesis has occurred but prior to the start of prophase. The cell synthesizes proteins and continues to increase in size. Note that the G in G2 represents gap and the 2 represents second, so the G2 phase is the second gap phase.
In the latter part of interphase, the cell still has nucleoli present.
The nucleus is bounded by a nuclear envelope and the cell's chromosomes have duplicated but are in the form of chromatin.
In animal cells, two pair of centriolesformed from the replication of one pair are located outside of the nucleus.
★IN LATE PROPHASE
The nuclear envelope breaks up.
Polar fibers, which are microtubules that make up the spindle fibers, reach from each cell pole to the cell's equator.
Kinetochores, which are specialized regions in the centromeres of chromosomes, attach to a type of microtubule called kinetochore fibers.
The kinetochore fibers "interact" with the spindle polar fibers connecting the kinetochores to the polar fibers.
The chromosomes begin to migrate toward the cell center.
★Anaphase -
In anaphase, the paired chromosomes(sister chromatids) separate and begin moving to opposite ends (poles) of the cell. Spindle fibers not connected to chromatids lengthen and elongate the cell. At the end of anaphase, each pole contains a complete compilation of chromosomes.
CHANGES THAT OCCUR IN ANAPHASE
The paired centromeres in each distinct chromosome begin to move apart.
Once the paired sister chromatids separate from one another, each is considered a "full" chromosome. They are referred to as daughter chromosomes.
Through the spindle apparatus, the daughter chromosomes move to the poles at opposite ends of the cell.
The daughter chromosomes migrate centromere first and the kinetochorefibers become shorter as the chromosomes near a pole.
In preparation for telophase, the two cell poles also move further apart during the course of anaphase. At the end of anaphase, each pole contains a complete compilation of chromosomes.
Cytokinesis (the division of the original cell's cytoplasm) begins and continues through telophase.
Telophase -
CHANGES THAT OCCUR IN TELOPHASE
The polar fibers continue to lengthen.
Nuclei (plural form of nucleus) begin to form at opposite poles.
The nuclear envelopes of these nuclei are formed from remnant pieces of the parent cell's nuclear envelope and from pieces of the endomembrane system.
Nucleoli (plural form of nucleolus) also reappear.
Chromatin fibers of chromosomes uncoil.
After these changes, telophase/mitosis is largely complete and the genetic contents of one cell have been divided equally into two.
CYTOKINESIS
Cytokinesis is the division of the cell's cytoplasm. It begins prior to the end of mitosis in anaphase and completes shortly after telophase/mitosis. At the end of cytokinesis, two genetically identical daughter cells are produced
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Answered by
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According to the Cell Theory, new cells are only created by the division of existing cells. In particular, mitosis is perhaps the most dramatic stage[1] of the cell cycle as it involves both the disintegration and reorganization of the components of the cell.
Mitosis, by definition is a type of cell division that involves only the somatic cells (any cell of a living organism other than the reproductive cells).
In this process, the growth of the organism itself and the repair of any damaged tissues are ensured by continuously dividing cells. Mitosis is also the process by which lower eukaryotic organisms multiply through asexual reproduction (i.e. budding and use of runners).
In simpler terms, during mitosis, a single cell gets divided into two identical daughter cells.
The main purpose of mitosis is to allow growth of new cells and also to replace the repaired or worn-out cells.
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