During a cytological study conducted on the chromosomes of the insects, it was observed that only 50% of the sperms had a specific structure after spermatogenesis. Name the structure and write its significance in sex determination of insects?
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Answers
The specific structure after spermatogenesis is termed as X body/ X factor/ X chromosome
Significance of sex determination in insects is In insects the sex chromosome consists of XX female; XO –Males
In this system, there is only one sex chromosome, referred to as X.
Males only have one X chromosome (X0), while females have two (XX). The zero (sometimes, O) signifies the lack of a second X.
Maternal gametes always contain an X chromosome, so the sex of the animals’ offspring depends on whether a sex chromosome is present in the male gamete. Its sperm normally contain either one X chromosome or no sex chromosomes at all.
In a variant of this system, most individuals have two sex chromosomes (XX) and are hermaphroditic, producing both eggs and sperm with which they can fertilize themselves, while rare individuals are male and have only one sex chromosome (X0). The model organism Caenorhabditis elegans—a nematode frequently used in biological research—is one such organism.
Some Drosophila species have X0 males.These are thought to arise via the loss of the Y chromosome.