9.2 meiosis & genetic variation Flashcards
compare mitosis to meiosis. (3)
2 diploid / 4 haploids
same chromosome num. / halved
in autosomal cells / gamete development
asexual / sexual
what type of daughter cells are produced by meiosis?
genetically different
describe the process of meiosis 1.
1) homologous chromosomes pair up along the equator to form a bivalent
2) spindle fibers attach to 1 side of the centromere only
3) chromatids from different chromosomes of homologous pair crosses over & exchange genetic material by forming a chiasma
4) homologous pairs separate
describe the process of meiosis 2, compared to mitosis.
just like normal mitosis; sister chromatids line up with spindle fibres attached to both side of centromere
how does crossing over of homologous chromosomes impact the genetic makeup of the daughter cells?
new genetic combinations of maternal & paternal alleles