MITOSIS AND MEIOSIS Flashcards
what are the two basic stages of the cell cycle?
interphase and mitosis
what is the difference between M phase and interphase
in interphase the cell is growing and making DNA copies
in m phase the cell divides by separating its DNA and creates two new cells
what happens during the g1 phase
rapid growth
what happens during the g2 phase
manufacture of cell organelles and cell parts needed for cell division
what happens during the S phase
duplication of DNA
process of mitosis
(Interphase)
Prophase
Metaphase
Anaphase
Telophase (Cytokinesis)
what is the process of the cell cycle
interphase: g1, s phase, g2
mitosis (PMAT)
what is cytokinesis
a single cell divides into two cells; the cytoplasm becomes separated
what are the two main checkpoints in the cell cycle
g1 checkpoint and g2 checkpoint (and spindle assembly)
what should you check for in g1
cell size
nutrients
growth factors
DNA damage
what should you check for in g2
cell size
DNA replication
what should you check for when spindle fibers assemble
chromosomes attaching to spindle
what does nuclear division mean
nuclear division happens in the nucleus
what does cytoplasmic division mean
division that happens in the rest of the cell
why does DNA exist as chromatin in interphase
it gives easier access to the protein
why does DNA condense during mitosis
the DNA becomes easier to separate
what happens in prophase
nucleolus and nuclear membrane disappear
chromatin coils to form visible chromosomes
threadlike spindle forms between the pair of centrioles
centrioles travel to opposite ends of the cell
what happens in metaphase
sister chromatids line up in the middle of the cell (two sister chromosomes form double chromosomes)
anaphase
sister chromatids separate and are now considered 2 single chromosomes
telophase
centrioles and spindle fibers begin to disappear
chromosomes turn back into the hard to see chromatin
nuclear membrane and nucleolus re-appear
chromatin
loosely coiled DNA (only in non-dividing)
chromosomes
tightly coiled DNA (only in mitosis)
sister chromatids
exact copy of chromosomes
centromere
location where chromosomes are attached
kinetochore
protein that motor protein can grab
centriole
made of microtubules arranged in perpendicular cylinders
found only in animal cells
migrate to opposing sides to make sure daughter cells get right amount of chromosomes
mitotic spindle
rips chromosomes apart
microtubules
helps develop the mitotic spindle
what are the differences between plant and animal cell division
plants:
plants have cell walls
they don’t have centrioles to they attach to the cell wall
plants can’t pinch so they have to build a new cell wall to separate the new cells
animals:
humans are “squishy”
they have centrioles
humans only have to pinch in the middle during cytokinesis to separate the new cells
what do some anti-cancer drugs target
kinetochore so they can’t separate the chromosomes
what two things enable chromosomes to move toward the poles during anaphase
kinetochore and motor proteins
mitosis in mitotic spindle
prophase: centrioles migrate to opposite ends of the cell=poles
spindle fibers attach to chromosomes
metaphase: centromere of sister chromatids are arranged to face opposite poles
chromosomes lined up in the middle of the cell
anaphase: kinetochore microtubules shorten
motor protein move the chromosomes along the microtubules
non-kinetochore lengthen=cell elongates
telophase (end of nuclear division) cytokinesis (cell division)
spindle fibers break down
how does cancer relate to the cell cycle
cancer develops when cells lose the ability to regulate their cell cycle
what are hallmark characteristics of cancerous cells
immorality
lack of contact inhibition
loss of intended function
what are proto-oncogenes and what does it do
they make proteins properly regulate their cycle and speeds up the cell division
what are tumor suppressor genes and what does it do
they make tumor suppressor proteins that destroy cancerous cells and slows down cell division
