However, in the form of N2, nitrogen is unusable by all organisms except for a few primitive bacteria that are capable of converting N2 gas to ammonia (NH3). This process of conversion is called nitrogen fixation, and makes the nitrogen available for use by organisms.
1 Simple carbohydrates are often used as building blocks of larger, complex carbohydrates. 2  The empirical structure of simple carbohydrate is C 6 H 12 O 6 or (CH 2 O) 6 while that of complex carbohydrate is (C 6 H 10 O 5) n, in which ânâ is the number of monomer units.
There are three main types of carbohydrates: 1. Simple carbohydrates (sugars): Sugar is the simplest form of carbohydrate. Simple carbs can be digested very quickly. Examples are cereals, honey, molasses, brown sugar, soft drinks, sweets snack bars, corn syrup, male syrup, biscuits, cakes. 2.