Genetics ch2

interphase I

chromosomes are relaxed and indistinguishable as diffuse chromatin

prophase I stages

leptotene, zygotene, pachytene, diplotene, diakinesis

leptotene

chromosomes condense and become visible

zygotene

chromosomes continue condensing, homologous chromosomes pair up, synapsis occurs. bivalents or tetrads occur here

pachytene

SNC (synaptonemal complex) develops, chromosomes become shorter and thicker

diplotene

centromeres of paired chromosomes move apart but 2 homologs remain at chiasma

diakinesis

chromosomes condensing, nuclear membrane breaks down, spindle forms

metaphase I

Independent assortment occurs here

anaphase I

homologous chromosomes separate

interkinesis

between meiosis I and II where nuclear membrane reforms and chromosomes relax, spindle breaks down

metaphase II

individual chromosomes line up in middle

anaphase II

sister chromatids separate

prophase I

crossing over occurs here

Diplotene

centromeres of paired homologs move apart

zygotene

homologous chromosomes pair up and begin synapsis

nuclear membrane breaks down

diakinesis

chromosomes start to condense and become visible

leptotene

spindle forms

diakinesis

Synaptonemal complex develops

pachytene