Test Four Cell Cycle And Division Flashcards
In mammal, how long cell divide
1 hour
M phase contains both
Mitosis and cytokinesis
Mitosis is
The division of nucleus
Cytokinesis is
Division of cytoplasm
Interphase contains
S phase, G phases
S phase is
Synthesis and replication of nuclear DNA
what are the different types of G phases
G, G1, G2
The central control system of cell cycle helps
Regulate start of each phase
Central control system is regulated by
Feedback using check point
Purpose of G1 check point
Extracellular environment
G2 checkpoint
DNA damage repair
Mitotic checkpoint
Microtubules attached and occurs during middle of mitosis
Function of cyclins
Regulation cyclic machine by repeating activation/ inactivation of proteins
Cyclins turn off and on by
Binding/ releasing to cyclic dependent kinases
What dephosphorylates Cdks
Phosphatases
What pushes the cell into the S phase
S cyclins bind to S-Cdk and G1 cyclins binds to C1-Cdk
G1 cyclins binds to G1 Cdks to stimulate
Cell division
What targets the degredation of cyclin protein
Cyclical proteolysis
How are ubiquitin chains added to cyclins
Anaphase promoting complex (APC)
Cyclins are directed to proteosomes for destruction by
Ubiquitin chains attaching to cyclins
What stops or slows an unprepared cell before the cell cycle
Cdk inhibitors
Example of Cdk inhibitor
P27
What molecule promotes the cell cycle
Mitogens
How to stop the cell cycle
Destroying kinases
What binds to the origins of replication to start the S phase
ORC
ORC binds to what after binding to origin
Cdc6
Function of Cdc6
Causes other proteins to come together to form a pre-replicative complex and start DNA replication
What holds sister chromatids together
Cohesin rings
If DNA is damaged, what gene regulatory protein is activated
P53
Activation of p53 leads to transcription of
P21
P21 binds to
G1/S-Cdk and S-Cdk to stop cell cycle from continuing
M-Cdk triggers
Chromosome condensation and assembles mitotic spindle
What activates M-Cdk
M cyclin
How does M cyclin activate M-Cdk
Protein phosphatases that remove inhibitory phosphates
Condensins are
Help chromosomes condense by assembling around each chromatid
What separates chromosomes
Mitotic spindles
Cytokinesis involves what to divide cytoplasm
Contractile ring made up of myosin and actin
M phase consists of
Prophase, prometaphase, metaphase, anaphase, telophase and cytokinesis
How many centrosomes during mitosis
2 since one is replicated
When do centrosomes form asters or radial microtubules
Interphase and beginning mitosis
What part of mitotic spindle goes to plasma membrane
Positive end
What part of mitotic spindle goes toward centrosome
Negative end
Microtubule associated proteins (MAPs) bind and stabilize
Microtubules
During Mitosis, MAPs prevent stabilizing by
Being phosphorylated
What molecule shrinks microtubules
Catastrophins
Do plants have centrosome
Nope
What are centrosomes
Where microtubules grow out of
What occurs during prophase
Centrosomes move in different directions by microtubules pushing them apart
What occurs during prometaphase
Nuclear envelope disappears, microtubules bind to chromosomes
What part of microtubules grab center of chromosomes
Kinetochore microtubules
What are the three classes of microtubules in mitosis
Aster, kinetochore, and interpolar
Function of aster microtubules
Explores
Function of kinetochore microtubules
Bind to chromosomes
Function of interpolar microtubules
Control mitotic spindle
What occurs during metaphase
Chromosomes line up at equator and play tug of war
What occurs during anaphase
Sister chromatids pull apart by APC breaking cohesins
What separates cohesins
Separase
How to activate separase
Securin told by APC to release separase
What are the two stages of anaphase
A and B
What is anaphase A
Kinetochore microtubules pull apart chromosomes
What is anaphase B
Separate the centrosomes
What occurs during telophase
Daughter chromosomes separated and vesicles form around
What forms the nuclear lamina
Lamins are dephosphorylated
What makes the chromosomes decondense during telophase
Nuclear proteins
What organelles duplicate during mitosis
Mitochondria and chloroplasts
Organelles that don’t duplicated are separated by what for cytokinesis
Microtubules
The cleavage furrow forms during what mitotic stage
Anaphase