Which one of the following sex determination systems is found in honey bee?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Haplodiploid type
Option (1) XY type — Incorrect. In the XY type the female is XX and the male is XY. It is found in humans and Drosophila.
Option (2) Z and W type — Incorrect. In the ZW type it is the female that has two different sex chromosomes (ZW), and the male is ZZ. It is found in birds.
Option (3) Haplodiploid type — Correct. The honey bee has no sex chromosomes. Sex depends on whether the egg is fertilised. So a female carries two sets of chromosomes (diploid) and a male only one set (haploid).
Option (4) XO type sex — Incorrect. In the XO type the male has only one X chromosome and no Y, while the female is XX. It is found in grasshoppers.
NCERT Extract:
Sex Determination in Honey Bee – “The sex determination in honey bee is based on the number of sets of chromosomes an individual receives. An offspring formed from the union of a sperm and an egg develops as a female (queen or worker), and an unfertilised egg develops as a male (drone) by means of parthenogenesis. This means that the males have half the number of chromosomes than that of a female. The females are diploid having 32 chromosomes and males are haploid, i.e., having 16 chromosomes. This is called as haplodiploid sex-determination system and has special characteristic features such as the males produce sperms by mitosis (Figure 4.13), they do not have father and thus cannot have sons, but have a grandfather and can have grandsons.”
Figure 4.13 Sex determination in honey bee