Question

In humans, there are _______ autosomal linkage groups, plus an X and Y chromosome linkage group.

Select one:

a. 23

b. 46

c. 22

d. 92

Answer 1

Option C 22 is correct.

Humans have 23 pairs of chromosomes. In these 23 pairs 22 pairs are autosomes. These are those chromosomes which do not carry sexual characters of a person and are common in males and females. In these 22 pairs, every chromosome is similar to 1 other chromosomes, so they are said to be in pairs. One pair is allosome. It is the chromosomes which determines the sex and sexual characteristic of a person. Here, in female, the pair may have both same chromosome i.e. XX but in males the 2 chromosomes of the pair are different i.e. X and Y.

Linkage groups are all the gene in one chromosome. Since there are 22 types of autosomal chromosomes, the number of autosomal linkage groups are 22. The allosomes are of 2 types X and Y. So, they have their own linkage groups. So, a male ( 22 pair autosomes + XY) consists of 22 (autosomal linkage) + 1 ( X linkage) + 1 ( Y linkage ) = 24 linkage groups and females ( 22 pair autosomes + 1 pair X chromosome) consists of 22 ( autosomal linkage) + 1 ( X linkage) = 23 linkage groups.