Course Guide Chapter 11: Cell Division- Mitosis Flashcards
What happens during G1 of interphase?
rapid growth and metabolic activity; centrioles replicate in the middle of microtubule organizing centers (MTOC) with microtubules radiating from the center
What happens during S phase of interphase?
chromosomes replicate along with their proteins but are still loosely dispersed as chromatin
What happens during G2 of interphase?
growth and final preparation; all organelles and membranes are duplicated during interphase
What happens during prophase of mitosis?
preparation for cell division occurs; nucleolus disappears; chromatin gets denser and forms chromatids; two pairs of centrioles move to opposite poles
What happens during prometaphase of mitosis?
the nuclear envelope fragments and disappears; microtubules of spindle fibers are connected to the chromosome at the kinetochore
What happens during metaphase of mitosis?
sister chromatids of replicated chromosomes are aligned in the middle of the cell at the metaphase plate
What happens during anaphase of mitosis?
the centromere of each chromosome divides; each newly formed chromosome moves apart to separate the sister chromatids into two single-stranded chromosomes
What happens during telophase of mitosis?
two nuclei form to separate sister chromosomes; chromosomes loosen to become chromatin again
What happens during cytokinesis of mitosis?
cell splits into two
How do cyclin and CDK serve as major components controlling check points?
Maturation promoting factor (MPF) is a combination if cdk and cyclin that promotes DNA synthesis and mitosis. Depending on the level of cyclin concentration, it binds to cdk. This stimulates autophosphorylation of cdk and depending on the phosphorylation status of S-MPF and M-MPF, DNA synthesis or mitosis occurs
