CBSE Class 12-science Answered
Linked genes usually do not assort independently but remain together in the gametes and the offspring give a dihybrid ratio of 3:1 instead of the normal ratio of 9:3:3:1. In our cross, if the ratio obtained is 3:1, it implies that the 75% of the cattle were black and 25% was white. Out of the 75% cattle which was black, 25% died after birth since the cattle that died was black in colour. This shows that 50% of the cattle that survived was black and the rest 25% was white.
Basis these assumptions, the probable genotype of the parent cattle which satisfies the above cross requirement is-
Indian breed – BBDDZz
Australian breed- bbDDZz,
where B and D are linked genes.
So, the correct answer is option C.
LinkageThis video talks about linkage of genes
Crossing OverThis video talks about crossing over in chromosomes
Sex Determination in animalsThis video talks about sex determination in different organsism
Chromosomal Theory of InheritanceThis video talks about the chromosomal theory of inheritance