Question

The sex determination pattern in honeybee is called
A. Female haploidy
B. Haplodiploidy
C. Gametic diploidy
D. Gametogony

Answer 1

Hint: The males develop from unfertilized eggs and females develop from fertilized eggs.

Complete answer: Honeybees sex is normally determined by the fertilization or non-fertilization of eggs, rather than the presence or absence of sex chromosomes.
In honey bees, the male is haploid while the female is diploid.
Male insects are haploid because they develop partheno-genetically from unfertilized eggs.
The phenomenon is called arrhenotoky.
Females grow from fertilized eggs and are hence diploid.
Haplodiploidy occurs in some insects like bees, ants, and wasps.

Additional information: Diploid queen has 32 chromosomes and the haploid drones have 16 chromosomes. Drones produce sperm cells that contain their entire genome, so the sperm are all genetically identical except for mutations.
1. The male bees' genetic makeup is therefore entirely derived from the mother, while the genetic makeup of the female worker bees is half derived from the mother and half from the father.
2. In honey bees when the father is haploid all the sperms are identical (except for a small number where gene mutations have taken place in the germline). So, all-female offspring inherit the male's chromosomes.
3. If the female has mated with only one male, all her daughters share a complete set of chromosomes from that male.
4. In Hymenoptera, the males generally produce enough sperm, even the female can use those sperms from her spermatheca for her whole life after a single mating event with that male.
5. The isolation of the sex determination locus in honey bees led to the identification of the complementary sex determiner (CSD) gene.
6. The CSD gene product is necessary for female development because the inactivation of the CSD gene product in female embryos causes a full switch into male development.
Recently, the target of the CSD gene product was identified as the feminizer (fem) gene.

So, the answer is B. Haplodiploidy

Note: The fem transcript splice differently in males and females, so that only female cells have a functional fem gene product. In males, splicing introduces a stop codon into the fem coding sequence.