mitosis Flashcards
what does a cell have to do before it divides
replicate its DNA
what are homologous chromosomes
genetic info thats the same but from two different parents
what do non dividing chromosomes look like
single chromatids
what is the pinch in a 2 chromatid chromosome
centromere
what protein holds two chromatids together
kinetochore
what are the 4 steps to DNA replication
unwinding
unzipping
building new strands
repackaging
what unzips dna
dna helicase
what joins 2 strands of DNA
dna ligase
what are the three types of DNA mutation / error
insertion
substitution
deletion
what are the 3 phases of interphase
G1
S
G2
what happens in G1 (2)
growth and metabolism
building of organelles
what happens in the S phase
DNA replication
what happens in the G2 phase (3)
growth
microtubules are made
contractile ring making
prophase (2)
chromatin condenses
spindles form
metaphase
chromosomes line up at the metaphase plate
anaphase
chromosomes separate and go towards opposite poles
telophase / cytokinesis
two cells are formed
where do microtubules form from
centriole
what phase does the nuclear envelope break down
prophase
what phase do microtubules depolymerize
anaphase
what makes the cleavage furrow
actin and myosin
what are 3 things that happen before a cell divides
enough cytoplasm
stimulated by growth factor
neighboring cells die
when do cells stop dividing (2)
when theyre snug with their neighbors
growth/ nutrients are withdrawn
what is contact inhibition
cells stop dividing because they come into contact with other cells
what is one bad thing that can happen if cells start dividing or stop dividing when they aren’t supposed to
cancer
when is the first checkpoint
G1
when is the second checkpoint
G2
when is the last checkpoint
what is it called
mitosis
M checkpoint
what is cancer
unregulated cell growth
what acts like breaks to slow down damaging mutations
tumor suppressors
what needs two damaged copies to cause cancer
tumor supressor genes
what acts like an accelerator to cause damage
proto-oncogenes
what only needs one damaged copy to cause cancer
porto-oncogenes
where are tumor suppressor genes found
the nucleus
where are port-oncogenes found
cytoplasm
what’s another name for genes
discrete factors
what is genotype
genetic makeup
what is phenotype
how genetic makeup is expressed
when are alleles separated
when are they rejoined
gamete formation
fertilization
is what Mendel assumed about recessive and dominant traits true about most genes
no
polygenetic inheritance
determined from dominant and recessive alleles
