Assertion: When the two genes in a dihybrid cross are situated on the same chromosome, the proportion of parental gene combinations is much higher than nonparental type.
Reason: Higher parental gene combinations can be attributed to crossing over betweentwo genes.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and R is not the correct explanation of A
C. A is true but R is false
D. A is False but R is true

Answer

C

Explanation

When the two genes in a dihybrid cross are situated on the same chromosome. the proportion of parental gene combinations is much higher than non-parental type.
Higher parental gene combinations can.t be attributed to crossing over between two genes. Linkage can be defined as a phenomenon of inheritance of genes in which genes present on a particular chromosome show their tendency to inherit together.
Morgan and his group also observed and stated that even when the genes grouped on the same chromosome, some genes were very tightly linked, they showed very low recombination frequency (strong linkage). Whereas the genes that were loosely linked showed higher recombination frequency (weak linkage).