How many chromosomes are present in an unfertilized egg

An inactive repressor produced by regulator gene that does not block the operator site in the tryptophan Operon is called

$A$ : Nutritional mutant strain of pink mould is auxotroph.
$R$ : It is not able to prepare its own metabolites from the raw materials obtained from outside

The genes, which are confined to differential region of $Y$ chromosome only, are called

Balbiani discovered special type of chromosome from the salivary gland of Chironomus larva which are recognized by the presence of