Question
Question: Which among the following is incorrectly paired? A. SRY gene - X chromosome B. 2n–2 minus Null...
Which among the following is incorrectly paired?
A. SRY gene - X chromosome
B. 2n–2 minus Nullisomy
C. Nucleoid – prokaryotic
D. Polytene in chromosome – drosophila
Solution
Hint: SRY gene is a sex determining gene which helps in retarding the femaleness and induces maleness in human beings.
Complete answer:
The SRY gene should contain Y chromosome because the Y chromosome is responsible for maleness in humans that is it is responsible for the development of human testis SRY gene is used as testis determining factor which secretes protein firstly from DNA molecule we get mRNA which contains SRY gene then on the father translation of the SRY gene protein is formed and that protein enhances the development of the testes and starts retarding the female characters is Nullisomy known as the loss of chromosomes.
Normal humans have 46 chromosomes which can either be X chromosomes or Y chromosomes if a human is containing 23 X chromosomes and 23 Y chromosomes then it will be a human male and if the individual is carrying 23 X chromosomes and 23 X chromosomes so it will be a human female.
SRY gene is the characteristic gene of Y chromosomes this gene also acts as a transcription factor and also helps in binding and attaches to some specific DNA regions.
Testis determining factor is very helpful in the binding so it comes under SRY like box (SOX) family and it also acts as a transcription factor and also helps in the formation of good nights in males and develops the primary sex organs SRY gene gets into the play after 6 to 8 weeks of pregnancy when the foetus formation has took place and helps in helps in developing the male characters which are dominant in them.
So, the correct answer is A.
Note: SRY is the TDF which helps in the formation of seminiferous tubules too, Which is helpful in the secretion of the testosterone.