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 glucose it needs to function properly. Two types of carbohydrates exist: complex carbohydrates and simple carbohydrates. Complex carbohydrates take time to break down into glucose. Foods rich in complex carbohydrates and fiber are called good carbohydrates.arbohydrates provide your body with glucose it needs to function properly. Two types of carbohydrates exist: complex carbohydrates and simple carbohydrates. Complex carbohydrates take time to break down into glucose. Foods rich in complex carbohydrates and fiber are called good carbohydrates.