-nuclear envelope surrounds nucleus. -centrosome has duplicated. -chromatin has duplicated (but not yet condensed).
microtubule organizing center. has two centrioles. part of the mitotic spindle.
apparatus of microtubules that controls chromosome movement during mitosis. -includes centrosomes, spindle microtubules, and asters.
radial array of short microtubules extending from each centrosome.
chromatin condenses into sister chromatids; assembly of spindle microtubules begins, centrosomes migrate to opposite poles as spindle microtubules grow out from them.
a structure of proteins associated with specific sections of DNA at each centrosome. -a chromosome has 2 kinetochores facing in opposite directions.
nuclear envelope fragments; chromatids get kinetochores; some spindle microtubules attach to kinetochores and jerk back and forth; nonkinetochore microtubule attachments also form.
-centrosomes at opposite poles. -chromosomes line up at the metaphase plate, the midway point between the spindle's two poles. -kinetochores arranged so for each chromosome, one kinetochore attached towards each pole.
sister chromatids separate (cohesion proteins cleaved); each chromosome moves along kinetochore microtubules toward opposite poles. -microtubules shorten by depolymerizing at kinetochore ends. -nonkinetochore microtubules from opposite poles overlap and push against each other, elongating cell.
genetically identical daughter nuclei form at opposite ends of the cell; nuclear envelopes form; chromosomes become less dense; spindle dissolves.
what material is the metaphase plate made of?
nothing it is imaginary.
separation of cytoplasm occurs differently in animal and plant cells. -each new cell gets its share of cytosol, organelles, etc.
cytokinesis (animal cell)
cytokinesis occurs by cleavage; a process of forming a cleavage furrow, or contractile ring of actin microfilaments associated with myosin, that pinches the parent cell in two.
cytokinesis (plant cell)
cytokinesis occurs by forming a cell plate; coalesced vesicles containing cell wall materials, that eventually grows to fuse with membrane around cell, dividing cell into two.
centrosome, centriole, centromere
centrosome: microtubule organizing center that is part of the mitotic spindle. -centriole: this is one of the two bodies marking the location of the centrosome. -centromere: this is the tight point of connection between two sister chromatids (region of specific DNA sequences where chromatids attach most closely).