study guide part 1

Before a cell can enter M phase
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Terms in this set (25)
Before a cell can enter M phase
centrosomes and chromosomes must be duplicated.
Cells grow primarily during the
G2 of the cell-cycle
Once a cell decides to enter the cell cycle, the time from start to finish is ________the same in all eukaryotic cells. There is variation in certain stages depending on the cell-type. For example, in rapidly dividing embryonic cells that get smaller with each cell division G1 phase is eliminated
NOT
Adding colchicine to cells at the metaphase-anaphase transition would cause the chromosomes to __________ but the cell would not elongate because of the disruption in microtubules.
segregate
In the cell cycle, a mitotic Cdk is present during _________ phases in the cell cycle. Cyclins concentrations vary throughout the cell cycle.
all
When early G1 phase cells are fused with S-phase cells using polyethylene glycol (PEG)....
DNA replication happens in the G1 cells
The generation time for a particular cell type refers to....
the time it takes a cell to progress through a complete cell cycle
Kinetochores assemble onto chromosome centromeres during _______. Kinetochore Mts attach to kinetochores
late prophase
Progression through the cell cycle requires a cyclin to bind to a ____ because the binding of a cyclin to ______ is required for the _____enzymatic activity
Cdk
If cells under-expressed Mad or Bub proteins, then the APC would be_________because Cdc20 can't be bound and is available to the APC. Then chromatids not attached to the spindle could separate, resulting in non-disjunction.
inappropriately activated
The appearance that the spindle and sister chromatids are _______ at metaphase is misleading because each sister chromatid is being pulled toward its respective pole.inactiveActivities of microtubule motor protein during mitosis except includes:shortening kinetochore microtubules, pulling kinetochore microtubules in at centrosomes, pushing interpolar microtubules for anaphase, and pulling astral microtubules toward the cell cortexIf a cell lacks a protein required for a checkpoint mechanism that operates in G2....the cell would enter M phase under conditions when normal cells would not.Cyclins modulate the progression of cells through the cell cycle by directly______________ that are critical regulators of cell divisionactivating protein kinasesLevels of Cdk activity change during the cell cycle, in because......cyclin levels change during the cycle and CDks need cyclins for activity. The Cdk synthesis and degradation is not involved in regulating mitotic Cdk activityIf the Rb protein were mutated such that it could not be phosphorylated by cyclin-dependent kinases.....the cell will not be able to enter S phase.The eukaryotic cell G2-M checkpoint assesses the status of....DNA replicationMitotic Cdk-cyclin is active when it is.....singly phosphorylatedThe anaphase-promoting complex (APC) is....not continuously active throughout the cell cycleThe concentration of mitotic cyclin (M cyclin) falls toward the end of M phase as a result of.....ubiquitylation and degradationPhosphorylation of condensin is directly required for....chromosome condensationAt the end of DNA replication, the sister chromatids are held together by the....cohesinsIf a chemical that depolymerized microtubules were added to cells during mitosis...chromosomes would fail to line up during metaphaseThe Retinoblastoma (Rb) protein blocks cells from entering the cell cycle by...inhibiting cyclin transcriptionThe G1 DNA damage checkpoint involves the inhibition ofcyclin-Cdk complexes by p21