How is sex determined in human beings?
How is sex determined in human beings?
Human beings exhibit male heterogamy. In humans, males $(XY)$ produce two different types of gametes, $X$ and $Y$. The human female $(XX)$ produces only one type of gametes containing $\mathrm{X}$ chromosomes. The sex of the baby is determined by the type of male gamete that fuses with the female gamete. If the fertilizing sperm contains $\mathrm{X}$ chromosome, then the baby produced will be a girl and if the fertilizing sperm contains $Y$ chromosome, then the baby produced will be a boy. Hence, it is a matter of chance that determines the sex of a baby. There is an equal probability of the fertilizing sperm being an $\mathrm{X}$ or $\mathrm{Y}$ chromosome. Thus, it is the genetic makeup of the sperm that determines the sex of the baby. (figure)
Similar Questions
$A$ : $XO$ type sex determination is found in large number of insects.
$R$ : Some of the sperms bear the $X-$chromosome whereas some do not
$A$ : $XO$ type sex determination is found in large number of insects.
$R$ : Some of the sperms bear the $X-$chromosome whereas some do not
Match the items of column $I$ with column $II$
Column $I$
Column $II$
$(a)\; XX-XO$ method of sex determination
$(i)$ Turner's syndrome
$(b)\; XX-XY$ method of sex determination
$(ii)$ Female heterogametic
$(c)$ Karyotype$-45 $
$(iii)$ Grasshopper
$(d)\; ZW-ZZ$ method of sex determination
$(iv)$ Female homogametic
Select the correct option from the following
Match the items of column $I$ with column $II$
| Column $I$ | Column $II$ |
| $(a)\; XX-XO$ method of sex determination | $(i)$ Turner's syndrome |
| $(b)\; XX-XY$ method of sex determination | $(ii)$ Female heterogametic |
| $(c)$ Karyotype$-45 $ | $(iii)$ Grasshopper |
| $(d)\; ZW-ZZ$ method of sex determination | $(iv)$ Female homogametic |
Select the correct option from the following
- [NEET 2019]
In our society a woman is often blamed for not bearing male child. Do you think it is right ? Justify.
In our society a woman is often blamed for not bearing male child. Do you think it is right ? Justify.
While solving the problem of sex determination in large number of insects, it was observed that
While solving the problem of sex determination in large number of insects, it was observed that
Assertion : In humans, the gamete contributed by the male determines whether the child produced will be male or female.
Reason : Sex in humans is a polygenic trait depending upon a cumulative effect of some genes on $X-$ chromosome and some on $Y-$ chromosome.
Assertion : In humans, the gamete contributed by the male determines whether the child produced will be male or female.
Reason : Sex in humans is a polygenic trait depending upon a cumulative effect of some genes on $X-$ chromosome and some on $Y-$ chromosome.
- [AIIMS 2015]