Knowt
Mitosis notes
Cell divison
cell cycle
Interphase
Mitosis
cytokinesis
why the cell divide?
2 part of cell divison:
growth and repair
reproduction bring babies babies= of spring
reproduction cell divison types: mitosis and meiosis
mitosis
mitosis is the division of the nucleus of the cell and its content (identical cells)
46 chromosomes in all body cells
chromosomes
they have 2 chromatics 1 centromere( the middle) and they are sister chromatids
sister chromatids are chromatids that form the same chromosome
stages
the longest time in the cell spent in the preparation of cell division = interphase
Interphase
the cell spends 95% of its time in interphase
there are 3 phases in interphase
G1 2.S 3. G2
the cell cycle = life cycle of the cell
G0-phase
G0 phase is no cell division
G1-phase
extra growth
organelles replication
S-phase
S = synthesis
DNA replication
it starts with a mother cell the divides into 2 new doughter cells with 46 chromosomes each equaling 92 chromosomes in both
a mother cell is a cell that is going to divide into 2 creating 2 daughter cells
douplicated = 2 chromatids
unduplicated = single
appers only if the cell divide
G2-phase
preparation for cell division
Mitosis
the only cells that dont undergo mitosis are the nerve cell (brain)
the spindle fibers are used to push the chromosome to the middle of the cell
stages of mitosis
PMAT
prophase
metaphase
anaphase
telophase
prophase
nuclear membrane brake apart
chromosomes shorten and condense
centrioles move to opposite pole
centrioles move to opposite poles
metaphase
sister chromatids line up in the middle of the cell = cell equator
anaphase
sister chromatids pulled by the spindle fibers to opposite pole
each chromatid now is a seperated chromosome.
telophase
nuclear membrame reform
2 new nuclei are formed
chromosome un coiled.
cytokinesis
the physical process of separating the cells
animal cell: cleavage furrow is the line between the separating animal cells
plant cells: cells plate is the line between the separating plant cells
