Meiosis Test one Flashcards
what is the mnemonic saying for prophase 1 stages
leaping zebras pound down dunes
synaptonemal zipper complex begins to dissolve bivalent chromosomes still connected at chiasmata
diplotene
severing of centromeres in sister chromatids move to opposite poles
anaphase two
chromosomes recondense if needed, nuclear envelope breaks down spindle apparatus re appears
prophase two
membranes form around daughter cell (4)
telophase
what is another name for meiosis one
reductional division
bivalent pairs created (tetrad) maternal and paternal sides together X and Y chromosomes pair at PARs region recombination nodules appear along complex crossing over occurs between non sister chromatids
pachytene
kinetochores of sister chromatids attach to microtubules chromosomes not identical bc of crossing over
metaphase two
what are germ cells
cells destined for a specialized role in the production of gametes
tetrads line up along metaphase plate sister chromatids attach to fibers from same pole kinetochores fuse to have one on each sister pair
metaphase one
what is the end product of meiosis two
4 daughter cells (n) haploid
what two aspects in meiosis contribute to genetic diversity
chance governs which paternal or maternal homologs migrate to which pole crossing over in prophase one
chromosomes begin to thicken sister chromatids attached to centromere but not yet visible centrosomes begin to move towards opposite poles
leptotene
interphase between meiosis one and two is called
interkinesis
another name for meiosis two is
equational division
what is the first stage of prophase one
leptotene
what is the end product of meiosis one
2 daughter cells 2n
if homologs of a chromosome pair do not segregate during meiosis one what happens
non disjunction
chromosomes seek out homologous partner homologous pair becomes zipped together synapsis form synaptonemal complex
zygotene
what is synapsis
when homologous pairs become zipped together to form a complex
nuclear membranes form around chromosomes at each end of pole daughter nuclei contain one-half the number of chromosomes in original parent nucleus
telophase one
chiasmata dissolve maternal and paternal homologs move to opposite sides sister centromeres stay connected
anaphase one
what are the subgroups in prophase one
leptotene zygotene pachytene diplotene diakinesis
further condensation of chromatids can see tetrad non sisters still attached at chiasmata nuclear envelope breaks down microtubeles and spindles apparatus begins to appear
diakinesis
what happens after cytokinesis of meiosis one
short interphase no s phase
what are chiasmata
areas where crossing over occurred
