Question

Maize has 10 pairs of chromosomes. How many linkage groups does it have?
A) 20
B) 10
C) 5
D) 40

Answer 1

Hint: The total number of linkage groups in an organism equals to the number of autosomes in its haploid cell.Using this concept we will find out the linkages in the group.

Complete answer:
Mendel’s law of independent assortment is not universal. It holds good only for the characters Whose genes are located on different (nonhomologous) chromosomes. But there are always many more inheritable characters in an individual than there are chromosomes. Consequently, each chromosome must bear m genes. Since the chromosomes move as units during meiosis into the gametes, all the genes present in the same chromosome will segregate as a group, and travel together from generation to generation. The readiness of the genes present in a similar chromosome to stay together in the hereditary transportation is known as linkage. The genes located in the same chromosome are called linked genes and those present in different chromosomes are termed as unlinked genes. The principle of linkage explains why in the fruitfly (Drosophila melanogaster), the red eyes and grey body occur in the same individual. The reason is that the genes of red-eye color and grey body color lie in the same chromosome and, therefore, go together in the gamete and the next generation. Therefore, option B is the correct option here.

Note: Here is something easy to find out the answer is : The number of linkage groups is equal to the haploid set of chromosomes.