AS.020.305 Midterm: cell bio final study sheet (dragged)
Document Summary
Microtubule nucleation and assembly are enhanced in the regions around the condensed chromosomes. As microtubules assemble on condensed chromatin pointing in random directions, the coordinated actions of several motor proteins build a coherent bipolar spindle from the disorganized microtubule mass. Eukaryotic*cell*cycle*is*dividing*into*four*phases: chromosome duplication occurs during s phase. (s = dna synthesis. ) This takes 10-12 hours, which is about half of the total cell cycle time in mammals: after s phase, chromosome segregation and cell division occur in m phase (mitosis. ) Indeed, many cells remain permanently in g0 until they or the organism dies. If extracellular conditions are favorable and signals to grow and divide are present, cells in early g1or g0 progress through a commitment point near the end of.
