They are the primary energy source for all organisms. Carbohydrates are divided into many types. Some are called sugars. The most important sugar is glucose, because it is very important for brain cells. Mostly we get carbohydrates from plants.
Lipids or fats
They are the secondary source of energy for organisms. They also have protective and supportive functions in organisms. Plant and animals contain fat.
In the human body, excess fat can cause some disorders, such as arteriosclerosis, which is the accumulation of fat molecules on the walls of blood vessels.
Arteriosclerosis blocks the blood flow and may cause heart attack and even death.