Topic 1 Heredity: Law of Meiosis

Question 1

• As you should recall from the previous chapter, meiosis is the cell division process that accounts for genetic diversity, which arises due to the separation of homologous chromosomes. There are two main laws that define this separation.

Answer 1

Note

Question 2

• One member of each chromosome pair migrates to an opposite pole in anaphase I so that each gamete is haploid
• Basically, each gamete is left with one copy of each allele

Answer 2

Law of Segragation

Question 3

• The migration of homologues within one pair of homologous chromosomes does not influence the migration of homologues of other homologous pairs

Answer 3

Law of Independent Assortment

Question 4

• How do these laws differ? The Law of Segregation dictates that when we form gametes, we separate allele copies so the gametes can be haploid. Differently, the Law of Independent Assortment states that the separation of each pair of chromosomes is completely independent from the separation of any other pair. They each separate randomly, and the outcome of one separation has no influence over the separation of the other. The image shows both of these laws in action
• Independent assortment can be observed in a dihybrid cross of peas - the presence of new phenotype combinations indicates the genes for seed shape and color assort independently

Answer 4

Note