In melandrium the sex determination type is
$XX-XY$ type
$XX-XO$ type
$ZZ-ZW$ type
$XY-XO$ type
Heterogametic male condition does not occur in
Bird females have chromosome arrangement as
A family has five girls and no son. Probability of son as the $6^{th}$ child will be
Sex determination in Drosophila melanogaster is based on
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.