Understanding:
• Orientation of pairs of homologous chromosomes prior to separation is random
During metaphase I, homologous chromosomes line up at the equator as bivalents in one of two arrangements:
- Maternal copy left / paternal copy right OR paternal copy left / maternal copy right
This orientation of pairs of homologous chromosomes is random, as is the subsequent assortment of chromosomes into gametes
- The final gametes will differ depending on whether they got the maternal or paternal copy of a chromosome following anaphase I
As this random assortment will occur for each homologous pair, the number of possible gamete combinations are dependent on the number of homologous pairs
- Gamete combinations = 2n (where n represents the haploid number)
Random Assortment of Homologous Chromosomes
