Transcript Cell Division

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นำงศิณีวณ
ั ย์ พิทกั ษ์ทิม D5010264
นำยอภัย ดวงคำ M5010288
นำงสำววณัทกมล นำคณรงค์ M5010042
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มีโครโมโซมเป็ น
2n ( Diploid )
มีโครโมโซมเป็ น
n ( Haploid )
กระบวนกำรเพิ่มจำนวน
ของเซลล์มีกระบวนกำร
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Duplication of the
chromosome
Continued growth
of the cell
Division into
two cells
Rod-Shaped Bacterium, E. coli,
dividing by binary fission
Interphase
Mitotic phase /
M phase
 เพื่อเพิ่มจำนวนเซลล์ ร่ำงกำย (Somatic cell)
พบในสิ่งมีชีวติ ชัน้ สูง เช่ น พืช สัตว์
เป็ นกำรแบ่ งเซลล์ เพื่อกำรสืบพันธุ์ของ
สิ่งมีชีวิตบำงชนิด (Haploid/ Monploid)
The stage of mitosis division
Mitosis
Cytokinesis
Cellular metabolic activity is high ,
chromosomes and organelles are
duplicated, and cell size may increase.
Interphase accounts for 90% of the
time of each cell cycle.
G1 phase
S phase
G2 phase
G1 Phase:
Growth--the cell grows in size.
S Phase :
Prior to mitosis, the cell readies itself by duplicating
its chromosomes and other cellular contents.
- Before DNA synthesis, the cell’s chromosomes consist
of one chromatid.
- After DNA synthesis, the cell’s chromosomes consist
of dyads with 2 identical sister chromatids attached at
the centromere.
G2 Phase :
The cell prepares the enzymes and machinery for mitosis
Mitosis
1. Prophase
2. Metaphase
3. Anaphase
4. Telophase
Cytokinesis
G1 phase
S phase
G2 phase
Mitosis
- Chromatin
Chromosome
(two sister chromatids)
- Nuclear envelope breaks into fragments.
- Microtublues
Mitotic spindle.
- Some of the spindle fibers reach the
chromosomes and attachit.
- Nonkinetochore microtubules overlap
with those coming from the opposite pole
The chromosomes align at the equitorial
plate and are held in place by microtubules
attached to the mitotic spindle and to part
of the centromere.
During anaphase the mitotic spindle apparatus pulls the
chromatids of each chromosome apart by attaching to each
centromere. Note that the telomeres of each chromosome
point toward the cell’s equator.
Chromosomes begin to disperse. Spindle
fibers disperse. The nuclear envelope forms
again around the nuclei.
Cytokinesis begins--formation of daughter cells. In
animals, like the whitefish, a cleavage furrow, a
contractile ring of muscle like fibers, pinches the
cell into two.
Meiosis
Sexual reproduction occurs only in
eukaryotes. During the formation of
gametes, the number of chromosomes is
reduced by half, and returned to the full
amount when the two gametes fuse
during fertilization.
Meiosis is a cell division process in
organisms that sexually reproduce.
Human
Life
Cycle
Phases
of
Meiosis
meiosis I
meiosis II
Phases of Meiosis
Interphase
Meiosis II
Meiosis I
Prophase II
Prophase I
Metaphase II
Metaphase I
Anaphase I
Anaphase II
Telophase I
Telophase II
Crossing Over
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Comparison of Mitosis and Meiosis
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