MITOSIS Flashcards
What does mitosis produce
Two identical daughter diploid cells
What is mitosis for
Growth and repair
interphase has 3 stages
G1
S
G2
Growth 1 phase
organelles replicate (e.g mitochondria)
transription/translation (lots of protein synthesis)
cell size increase
Synthesis
chromosomes replicated
DNA synthesised
Growth 2
damaged chromosomes repaired
energy stores replaced
cell size increases
protein synthesis
after interphase what process begins
mitosis
some cells can enter G0 during interphase, why
cells may be fully differentiated so they stay at g0 forever
cell may be senescent (cant do mitosis sue to damaged DNA) so it enters g0
memory cells temporarily stay in g0 till infection arises where they reenter
G1 checkpoint
checks cell grown to right size
checks for DNA damage
if cells fail a checkpoint
pauses to repair
if unable enters aptosis (cell suicide)
g2 checkpoint
checks for DNA damage
sister chromatid
copied and og DNA touh at centromere
cell cycle order
ipmatc
prophase (start of mitosis)
chromosomes condenses and becomes visible
nuclear membrane starts to breakdown
spindles form
metaphase
chromosomes line up at cell equator
spindle fibres attach to centromeres
anaphase
chromosomes break at their centromere
spindle fibres shorten
pulling sister chromatids to opposite poles
telophase
chromosomes reach poles of cell
spindle fibres breakdown
nuclear membrane reforms around chromosomes
chromosomes uncoil into chromatin
nucleolus reappears in each nucleus
cytokenisis
central plasma membrane is pulled inwards by cytoskeleton
membrane pinches off and fuse to fom two seperate cells
difference in plant mitosis
plants dont have centrioles helping form spindle fibres
cells seperate by lining vesicles along center of cell which fuses together to form a cell membrane
m checkpoint
during metaphase to check spindle fibres formed correctly
