Class 12th Biology 2014 Set1 Delhi Board Paper Solution
Women are often blamed for producing female children. Consequently, they are ill-treated and ostracised. How will you address this issue scientifically if you were to conduct an awareness programme to highlight the values involved?
Women are never responsible for determination of the sex of a child. Moreover, it is not appropriate to ill-treat a woman for giving birth to a girl child, as both males and females are equally important for the balance of nature and continuity of our species.
All human-beings have 23 pairs of chromosomes. A human sperm (haploid) has 22 autosomes and one of the two types of sex chromosomes, i.e. either X or Y. On the contrary, human females have 22 autosomes that are exactly same as males and contain two X chromosomes. The sex of an individual is determined by the type of the sex chromosome (X or Y) contained by the sperm that fuses with the ovum.
If the fertilising sperm has an X chromosome, then the baby would be a female and if a sperm with Y chromosome fuses with the ovum, it will develop into a male child. Thus, males are responsible for determination of the sex of a child.
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(b) Spermatozoa get nutrition from Sertoli cells. (True/False)
(c) Leydig cells are found in ovary. (True/False)
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