cell division
process by which cells make more cells
binary fission
one prokaryotic cell divides to produce two daughter cells
steps of binary fission
- DNA is attached to cell membrane
- DNA is copied
- DNA molec. attached to cell membrane
- cell elongates/separate DNA attachment sites
- new call membrane and walls are synthesized
- two daughter cells formed
asexual reproduction
production of organisms where offspring inherits DNA from a single parent
mitosis
division of nucleus
cytokinsis
division of cytoplasm into 2 daughter cells
chromosomes
cellular structure in eukaryotes and prokaryotes that consist of single DNA molec.
cell cycle
period from when production of a new cell to the time it divides
m phase
parent cell divides into 2 daughter cells
interphase
copying DNA and cell growth, broken into 3 phases
g1 phase
cell prepares for DNA replication
s phase
DNA molec. copied
g2 phase
cell prepares for M phase (size and protein content of the cell increases)
sister chromatids
DNA in chromosome duplicated into 2 identical copies
centromere
constrictly holds together sister chromatids
g0 phase
cells that are not actively dividing
chromatin
highly organized complex of DNA, RNA, and proteins in chromosomes
prophase
1st stage of mitosis
mitotic spindle
groups of fibers made up of microtubules pull chromosomes to opposite ends of dividing cell
cntrosome
in animal cells, the mitotic spindle radiates outward
prometaphase
nuclear envelope breaks down and mitotic spindle attaches to the chromosomes
kinetochores
two protein complexes associated with the centromere of each chromosome
metaphase
when chromosomes are aligned in the middle of the dividing cell
anaphase
next stage of mitosis, sister chromatids separate
telophase
cell prepares for its division into 2 new cells
cancer
mechanisms in cell division fails = death of cell or uncontrolled cell division
cyclin-dependent kinases (CDKs)
activity depends on binding cyclins, allows cell cycle to progress
checkpoint
the activity required for the next step and pauses the cell cycle until preparations are complete or damage is repaired
DNA replication
duplicating a DNA molec.
apoptosis
cells that are programmed to die
p53 protein
DNA damaged by radiation activated that phosphorylates a protein