AP Bio Chapter 12 Part 3 Flashcards
Spindle fibers attach to the _________________ which attach to the ____________
Kinetochore, chromosome
Homologous
Same gene, same location, on different parent chromosomes
How does the kinetochore mediate the movement of chromatids
Kinetochore is attached to, microtubules break down which pulls chromosomes closer to the poles
Cytokinesis is the splitting of a cell into ____
2
How is cytokinesis visual in animals
A cleaves furrow, a “contractile ring” of microfilaments pitches the cell into two
How is cytokinesis visual in plants
Vesicles from both cells deposit a new cell wall (made of protein, carbs, etc) partition (the cell plate) in the middle of the cell.
In cytokinesis, how is organelle apportioned
Completely random
Why must the cell cycle be controlled by precise functions
So organ systems can’t be disrupted
When should cells divide
Only when they need to
What must a cell pass in order to divide
Certain checkpoints
What happens if cells pass checkpoint G1
They’ll divide
If they don’t pass G1?
They go to G0
Senescence
When the cell has stopped dividing (G0)
How is contact inhibition used?
To determine whether cells should divide at checkpoint
What are internal controls
Protein molecules that are present in varying concentrations during the cell cycle
What dies evidence suggest about internal controls
There are molecules present during cell cycle that causes cells to progress. Chemicals in cytoplasm triggers events to occur more rapidly when cells in different stages fuse –internal control
