Energy is required for maintenance of life. It is obtained by a process called

Energy is essential for the maintenance of life and is obtained through metabolism. Metabolism encompasses all chemical reactions within a cell, including those that transform energy to build structures and transport molecules. A critical component of metabolism is respiration, where organic compounds like glucose are broken down to provide energy in the form of ATP [1]. ATP serves as the universal energy currency for cellular processes such as muscle contraction and protein synthesis [2]. Maintenance of life specifically requires processes like nutrition and respiration to sustain biological functions [3]. While phagocytosis is a method of intake and decomposition is the breakdown of dead matter by external organisms, metabolism is the comprehensive internal process that governs energy acquisition and utilization in living systems. Nutrients taken from the environment are used in an organism's metabolism to live and grow.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > What you have learnt > p. 99
2. [2] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > ATP > p. 88
3. [3] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > What you have learnt > p. 98