cell division Flashcards
what happens in interphase
cell don’t divide
cells spend majority of time here
normal metabolic processes occur
what’s G1
proteins synthesised and organelles replicate
cells increase in size
what’s S
synthetic phase
DNA replicated
what’s G2
cells continues to grow in size
energy stores increase
DNA checked for errors
what’s G0
rest phase leaving the cell cycle
why do cells move to G0
some cells are differentiated that they may not be able to divide anymore
DNA of the cell is damaged
senescence – age
how do we control the cell cycle
checkpoints – control mechanism
monitors and verifies whether processes at each stage have been completed before the cell progresses into the next stage
what’s the G1 checkpoint for
checks cell size
nutrients
growth factors
DNA damage
what’s the G2 checkpoint for
check for cell size
DNA replication
DNA damage
what is the spindle assembly checkpoint for
check for chromosomes attachment to spindle
describe mitosis
process of cell division
describe prophase
chromatin fibres coil and condense to form chromosomes
nucleolus disappears
nuclear membrane breaks down
two centrioles migrate to opposite poles of the cell
spindle fibres attach to centromeres
describe metaphase
chromosomes moved to form plane at equator of the cell
called metaphase plate
describe anaphase
centromeres divide
chromatids separate and pulled to opposite poles of the cell by shortening spindle fibres
describe telophase
chromatids now chromosomes
nuclear envelope forms around new sets of chromosomes
chromosomes uncoil and nucleolus reforms
