In a honey bee hive, what determines whether an egg develops into a female or a male (drone)?

Correct Option

The correct option is

Whether the egg is fertilised or unfertilised.

Explanation

In honey bees, sex determination is governed by the haplodiploid system. This mechanism relies on the number of chromosome sets an individual receives, which is strictly determined by whether the egg undergoes fertilization.

Detailed Analysis

• Fertilized Eggs (Diploid): When an egg fuses with a sperm, the resulting zygote is diploid (2n). These fertilized eggs develop into females (either queens or workers).
• Unfertilized Eggs (Haploid): If an egg is not fertilized, it develops directly into a male (drone). This process of development from an unfertilized egg is known as arrhenotokous parthenogenesis. Males are haploid (n).

Analysis of Incorrect Options:

• The temperature of incubation.: Temperature-dependent sex determination is characteristic of certain reptiles (e.g., turtles and crocodiles), not insects like honey bees.
• The type of food fed to the larva.: The type of food (specifically the quantity of Royal Jelly) determines the caste differentiation among females (Queen vs. Worker), but it does not determine the biological sex.
• The size of the cell in the hive.: While queens selectively lay unfertilized eggs in larger cells, the cell size is a behavioral response, not the biological determinant of sex.

Key Takeaway: Honey bee sex is determined by haplodiploidy: females arise from sexual reproduction (fertilized eggs), while males arise from asexual reproduction (unfertilized eggs/parthenogenesis).