Reduces the number of chromosomes in new cells to half the number in the original cell Produces gametes (sperm and egg cells)
In animal cells, a ring of actin fibers (microfilaments are composed of actin) forms around the cell equator and contacts, pinching the cell in half. When the new wall joins with the existing side wall, the 2 cells have become separate. Cell membranes form along the surfaces of this wall. In plant cells, a new cell wall made of cellulose forms between the 2 new nuclei, about where the chromosomes lined up in metaphase. Plant and animal cells divide the cytoplasm in different ways. The cytoplasm is divided into 2 separate cells, the process of cytokinesis.Ĩ Cytokinesis The organelles (other than the chromosomes) get divided up into the 2 daughter cells passively: they go with whichever cell they find themselves in. The spindle disintegrates The nuclear envelope re-forms around the two sets of chromosomes. The chromosomes are at the poles of the spindle. Then the spindle fibers contract, and the chromosomes are pulled to opposite poles, towards the centrosomes.ħ Telophase In telophase the cell actually divides. At this point, each individual chromosome goes from: 1 chromosome with 2 chromatids to: 2 chromosomes with one chromatid each. Everything is aligned for the rest of the division process to occur.Ħ Anaphase In anaphase, the centromeres divide. The spindle starts to form, growing out of the centrosomes towards the chromosomes.ĥ Metaphase Metaphase is a short resting period where the chromosomes are lined up on the equator of the cell, with the centrosomes at opposite ends and the spindle fibers attached to the centromeres. In prophase they separate and move to opposite ends of the cell. During interphase, the pair of centrosomes were together just outside the nucleus.
The double membrane that surround the nucleus dissolves into a collection of small vesicles, freeing the chromosomes to use the whole cell for division 3. The proteins attached to the DNA cause the chromosomes to go from long thin structures to short fat one, which makes them easier to pull apart. Pada tanaman mitosis terjadi pd sel-sel meristematis, misalnya kambium, ujung-ujung akar, dan ujung batang.Ĥ Prophase In prophase, the cell begins the process of division.ġ. Mitosis memegang peranan dalam pertumbuhan dan perkembangan organisme. Presentation on theme: "MEKANISME SEL DAN SIKLUS HIDUP TANAMAN"- Presentation transcript:Ģ MITOSIS Istilah mitosis : proses yg menghasilkan dua sel anak yg identik.
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