The body uses mitosis for growth as our bodies mature and for repair. Before the actual mitosis, the cell is prepared to make sure it is ready to undergo the process. Then the cytoplasm begins to divide around the two new nuclei - which is called Cytokinesis Cytoplasmic Division. Nucleolus disintegrates and disappears completely. Note that the G in G1 represents gap and the 1 represents first, so the G1 phase is the first gap phase.
The first and longest phase of mitosis, prophase, can take as muchas 50-60% of the total time required to complete mitosis. They are separated at the kinetochores. During interphase the chromosomes are dispersed in the nucleus and appear as a network of long, thin threads or filaments, called the chromatin. Kinetochores are formed in this stage when proteins connect to the centromeres. First, we will learn how to identify the phase by looking at it in both a diagram and an actual cell. Mitosis Anaphase Source: Wikimedia The gradual shift from metaphase to anaphase is characterized by the breaking of the link between the sister chromatids that are about to migrate to the separate poles of the cell. During this process, the microtubules alternately and quickly assemble and disassemble as they try to find their ways toward the kinetochores found at the centromeres of each sister chromatid.
During anaphase the two chromatids of each chromosome separate and move to opposite poles, as if pulled along the spindle fibers by the centromeres. In general, there are four main phases in the mitosis process. Also during prophase the spindle begins to form. A spindle of microtubules thread-like structures made of tubulin polymers is formed from pole to pole from the centrioles in animal cells and from pole to centromere. The original cell is the called the parent cell, and the new cells are called daughter cells. Imagine those football players lined up at the half-line separating and running to opposite sides of the football field.
What is done during prophase is re-done in telophase. What is done during prophase is re-done in telophase. A nuclear envolpe forms around them. What is done during prophase is re-done in telophase. There are two different kinds of cell growth: mitosis and meiosis. If otherwise, the cell will have to stop mitosis until the problem is fixed.
The chromosomes uncoil to assume their dispersed distribution within the interphased nucleus. Each chromosome splits into two chromatids Fig. For example, in prophase the nucleus breaks down, in telophase the nucleus is re-formed. There are now two cells where there was once only one. Nucleolus also starts dissolving and disappearing. The centrosomes are different between plant and animal cells.
Animal cells have centrioles which are tube like structures made of the protein tubulin. Anaphase: While in the anaphase stage of mitosis the centrioles will begin to pull each chromosome into two halves called sister chromatids. Spindle fibers will eventually act like cables to move the chromosomes around. Some sets of fiber run from one centriole to the other; these are the spindle fibers. Mitosis has four main phases: prophase, metaphase, anaphase, and telophase. Each tetrad is composed of four. During this phase, the chromosomes' two halves pull away from each other and move to opposite ends of the cell.
The final stage of mitosis is telophase. However, please remember that this is an education channel. This pulls the chromosomes, now split apart called the sisiter chromatids. Can you give any other examples? You can tell when the chromosomes are moving, because the spindle fibers are hooked to the middle of each chromosome so the tails of the chromosome trail behind. Nevertheless a number of mitotic stages can be defined: prophase B and 2 , metaphase C and 3 , anaphase mid 4 and late D and 5 , telophase E and cytokinesis F and 6. The chromosomes are lined up in the middle with each half positioned to go to opposite sides of the cell.
Spindle fibers disappear, cell ready to separate into daughter cells. The four stages of mitosis prophase, metaphase, anaphase and telophase are shown and described below. A nuclear envelope re-forms around each cluster ofchromosomes. During mitosis, a pair of chromosomes separate, creating two identical pairs of chromosomes and, in turn, two identical cells. Chromosomes become shorter and thicker. Resulted daughter cells have the same characters as were present in the parent cell. In animal cells cytokenesis is taking place and splitting the cell into two daughter cells.