1. prophase ( 92 chromosomes )
1. chromosomes are condenced
2. nuclear envelope is dissolved
3. mitotic spindle forms
what is the mitotic spindle made of?
microtubules
Metaphase ( 92 chromosomes )
spindle fibers attach to kinetochores pulling sister chromatids along the middle of the cell
chechoint- ensured metaphase is successful,
Anaphase ( 92 chromosomes )
spindle fibers contract separating sister chromatids
Interphase
where the cell does most of its work
( cell growth, DNA synthesis, more cell growth and checkpoints )
telophase
nuclear envelope formed with 42 chromosomes in each nucleus
chromosomes DEcondence
mitotic spindle breaks down
G1 phase of interphase
growth , gene expression, 46 chromosomes, checkpoint
S phase of interphase
synthesis of DNA, and DNA replication occurs in G2. after S phase there's 92 chromosomes
G2 phase
more growth, more gene expression, checkpoint ensuring DNA replication is successful and makes sure mitosis materials are available
why are some parts of the cell cycle longer than others?
because some are just more complex. like interphase where most of the cells work is being done like cell growth DNA synthase more cell growth and checkpoints. mitosis is just a division of the cell
Cytokinesis
cell divides ,(animal) actin squeezes the cell apart, ending up with 2 seperate cells each with 46 chromosomes
plant
cell wall cant be squeezed apart, plant forms cell plate btw 2 nuclei eventually forming a new cell wall. and then the whole cell cycle starts over
prokaryotic cell division
prokaryotes divide by binary fission
binary fission
1, cell grows 2, DNA replication, 3. cell grows more 4, cell splits in half
all happens VERY FAST, as fast as 20mins
meiosis
the reproductive method for germ cells
gametes
sperm, egg
goal of meiosis
diversity
goal of mitosis
identical cells
why does meiosis shuffle genes
to imrove species survival