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 have very simple chemical structures and are made of small molecules. 2  Complex carbohydrates have very complex structures while the molecules are large, unlike simple carbohydrates.
Simple carbohydrates are considered as the simple sugars which contain a few carbon atoms. There are two types of simple carbohydrates, namely; monosaccarides and disaccharides. The empirical formula for monosaccharide is C 6 H 12 O 6 or (CH 2 O) 6.