$X$ -chromosome or $X$ - body was first observed by.............
Mendel $(1901)$
Castle $(1910)$
Henking $(1891)$
Bateson $(1906)$
Give differences : Male heterogamety and Female heterogamety
Describe haploid diploid sex determination system ?
A couple has $6$ children-$5$ are girls and $1$ is boy. The percentage of having a girl on next time is
Describe the process of sex determination in humans.
A male child would be born to parents if