Why is the enzyme lactase necessary to digest dairy products?

The enzyme lactase helps digest dairy products through breaking it down into two simple sugars which as glucose and galactose. The body have difficulties in absorbing full lactose molecule thus the need for breaking it down into simpler sugars. This is why lactase is important as it splits the bond that holds the galactose and glucose. 

The element carbon is actually the chemical basis for all life. It is the most important because it can be used to form many essential compounds.

Carbon takes up almost 20% of the weight of an organism, and it is essential for them to live and grow. (Also to reproduce.)