Define the term metabolism. What is its benefit for living organisms? What are its types?

The sum total of all the chemical reactions occurring inside the living organism is called metabolism.All the activities like growth, reproduction, movements, responsiveness, development, etc., are due to metabolism.
Metabolism includes two stages, i.e., anabolism and catabolism. Anabolism includes all the building up reactions, e.g., Photosyntesis and catabolism constitutes breakdown reactions, e.g., Respiration.