Carbohydrates.
The most concentrated source
of calories comes from carbohydrates. Carbohydrates has three types: monosaccharide,
disaccharide and polysaccharide. These carbohydrates are from the combined
atoms of carbon that is one of the most important source of energy for an
organism. In most animals, carbohydrates are modified to become glucose or
blood sugar by the digestive system and delivered to many cells in the
organisms’ body that is used in many cellular activity.