The $lac \, y$ gene codes for which of the following?

The lactose present in the growth medium of bacteria is transported to the cell by the action of

Wild type $E. coli$ cells are growing in a normal medium with glucose. They are transferred to a medium containing only lactose as the sugar. Which one of the following changes takes place?

Match the following genes of the $Lac$ operon with their respective products.

$(a)\; i$ gene	$(i)\; \beta-\text{galactosidase}$
$(b)\; z$ gene	$(ii)\; \text{Permease}$
$(c)\; a$ gene	$(iii)\; \text{Repressor}$
$(d)\; y$ gene	$(iv)\; \text{Transacetylase}$

Select the correct option.

Differentiation of organs and tissues in a developing organism is associated with:

Provide definitions/explanations for the following terms: Splicing and Operator gene.