Group	Examples	Functions
Carbohydrate	Glucose  Glycogen	Short term energy source Transport form in animal Long term energy storage
Lipids	Fats and oils	Components of membranes Long term energy storage Insolation
Proteins	Enzymes  Sucrase and lactase  Keratin  Collagen	Organic catalysts  Digestive enzymes  Structural protein in hair  Structural protein in skin
Nucleic acids	DNA  RNA  ATP	Information molecule Molecule of heredity Director of metabolism involved in protein synthesis immediate source of energy for cellular work

 

Enzyme is a protein which speeds up the rate of chemical reaction without being destroyed by the reaction.