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.
Carbohydrates provide your body with the glucose it needs to function properly. There are two types of carbohydrates: complex and simple. Foods rich in complex carbohydrates and fiber are called good carbohydrates. Simple carbohydrates include foods with added sugars -- these are called bad carbohydrates.arbohydrates provide your body with the glucose it needs to function properly. There are two types of carbohydrates: complex and simple. Foods rich in complex carbohydrates and fiber are called good carbohydrates. Simple carbohydrates include foods with added sugars -- these are called bad carbohydrates.