$A$ man who carries a sex-linked gene on his $Y$ chromosome will transmit this gene to:

$A$ fruit fly is heterozygous for a sex-linked gene. It is crossed with a normal female fruit fly. The specific chromosome for the male enters the egg in the ratio of ............. (in $: 1$)

In chickens,which of the following is responsible for sex determination?

The following diagram shows sex determination in honeybees. How many chromosomes do $P, Q,$ and $R$ have?
$\quad\quad P \quad Q \quad R$

Give differences: Male heterogamety and Female heterogamety.

The $TDF$ gene is a.....