Question

State and explain the "law of independent assortment" in a typical Mendelian dihybrid cross.   (5)
OR
(a) How do the observations made during moth collection in pre- and post- industrialized era in England support evolution by Natural Selection?

(b) Explain the phenomenon that is well represented by Darwin's finches other than natural selection.
 

CBSE Class XII Biology Question Paper 2017

Answer 1

A dihybrid cross is a crossbetween individuals heterozygous at two different loci. Mendel'ssecond law is also known as thelaw of independent assortment. The law of independent assortment states that the alleles of one gene sort into gametesindependently of the alleles of another gene.