Question

Donkeys have a somatic chromosome number of 62. Hybrids produced by crossing donkeys and zebras are called zonkeys, are sterile, and have many characteristics intermediate between the two parental species. If a zonkey has 52 chromosomes, what is the somatic chromosome number of zebras?A) 52B) 31C) 62D) 21E) 42

Answer 1

The correct answer would be option E) 42.

Explanation:

The number of chromosomes present in the body cells typically is 2n or diploid which means a pair of the chromosome. The body cells or somatic cells are always diploid and two times more than the sex cells which called haploid. Haploid cells are produced during sexual reproduction.

In any offspring, half the number of chromosomes of the total pair of somatic chromosomes comes from both the parents. Similarly here the chromosome that derived from the donkeys is half of 62 that is 31, as it is already given that zonkeys have 52 chromosomes so the chromosome that come from the zebra would be 21 (52-31=21). hence the somatic chromosome number of the zebra would be 42 ( 2n =2 times of 21)

Thus, the correct answer would be option E) 42.