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Question: In humans, an egg involved in male child formation has the genetic constitution of A. 22 + X B. ...

In humans, an egg involved in male child formation has the genetic constitution of
A. 22 + X
B. 22 + Y
C. 44 + XY
D. 44 + XX

Explanation

Solution

Sex determination in humans was decided by the Y chromosome which holds a functional gene named SRY gene. When this gene is activated, the testosterone is created with an anti-mullerian hormone which ensures the development of the male reproductive system only. Humans have an XY Sex-determination system. Women have 2 X chromosomes while males have one X chromosome and one Y chromosome.

Complete answer: In humans, chromosome Y will be the main factor for sex determination.
In absence of the Y chromosome, the fetus will undergo the development of a female gamete and in the presence of the Y chromosome, the fetus will undergo the development of a male gamete
In humans, males can produce two types of gametes.
Gametes produced by males will have either 22+X chromosomes or they will have 22+Y chromosomes.
But females can only produce one type of gamete which will contain 22+X chromosomes in it.
So when gametes with 22+x chromosomes from males attached with females gamete with 22+X chromosome then it will result in a female child with 44+XX chromosome.
But when the male gamete with 22+Y chromosome attaches with the female gamete with 22+X chromosome then it will result in a male child with 44+XY chromosome.
That's during the formation of the zygote, mothers will provide only 22+X chromosomes.
So, the correct option will be an option (A).

Note: The sex of an early embryo is can't be determined because at an early stage (until the seven-week) the reproductive structure is not distinguished. Missing or having more sex chromosomes can lead to genetic disorders. Some of the basic examples of abnormality in the sex chromosome are Turner syndrome, Klinefelter syndrome. These abnormalities can include male infertility, premature ovarian failure, etc.