lecture 24 - mitosis Flashcards
what is chromatin?
DNA and proteins that make up chromosomes
in what form is DNA when the cell is not undergoing mitosis?
chromatin
2 main phases of the cell cycle
interphase and mitotic phase
what are the three stages of interphase?
g1 phase, s phase, g2 phase
which phase does cell growth occur at?
g1 phase
which phase does dna replication occur at?
s phase
which stage does the cell spend most of its life in?
interphase
what structure is made of microtubles?
mitotic spindle
what is the mitotic spindle?
separates chromosomes
what stage comes after prophase?
prometaphase
which phase does chromatin condense into chromosomes?
prophase
what happens to the nuclear envelope in prophase?
begins to breakdown
where are sister chromatids joined at?
centromere
when do spindle fibres attach to kinetochores?
prometaphase
what phase comes before metaphase?
prometaphse
what phase comes after metaphase?
anaphase
what form is DNA found in metaphase
condensed chromosome
what is happening to DNA in telophase?
DNA is condensing back into chromatin
what phase comes before telophase?
anaphase
what happens in anaphase?
sister chromatids are pulled to opposite poles
what are the main stages of mitosis?
prophase, prometaphse, metaphase, anaphase, and telophase
what is cytokinesis in animal cells?
division of the cytoplasm via cleavage furrow formed by actin and myosin
true or false - cell plate forms from vesicles, eventually becoming the cell wall in cytokinesis of plant cells
true
how is the cell plate formed in plant cells?
vesicles join together
what is happening to the nuclear envelope in telophase?
reforming
what form is DNA in prometaphse?
condensed chromosomes
what causes the cell to stretch in anaphase?
microtubules
what type of cell division occurs in bacteria?
binary fission
true or false - DNA condenses in bacteria
false
what type of protein moves DNA to opposite ends of the cell?
actin and tubulin
where does the mitotic spindle form in dinoflagellates?
outside the nucleus
what happens to the nuclear envelope in dinoflagellates during cell division?
stays intact
where does the mitotic spindle form in diatoms?
inside the nucleus
what happens to the nuclear envelope in diatoms during cell division?
nuclear envelope remains intact
what is the primary focus of cytokinesis in the cell cycle?
separate the cytoplasm into 2 daughter cells
what phase of the cell cycle is the shortest?
M phase
which structure is responsible for the separation of sister chromatids during mitosis?
mitotic spindle
during which phase of mitosis do the kinetochores attach to the microtubules of the spindle?
prometaphse
how many chromosomes are present in a human somatic cell?
46
true or false - somatic cells are involved in reproduction
false - gametes are involved in reproduction
why does the nuclear membrane have to breakdown?
allows spindle fibres to attach to the chromosome and move them around
which phase does the nuclear envelope fully breakdown?
prometaphse
in which phase does the cell elongate?
anaphase
what form does DNA stay in binary fission?
chromatin
