Final answer:
Metabolism is the complete set of chemical reactions that occur within cells to sustain life, including catabolic and anabolic reactions, making up a cell's complex biochemical processes.
Step-by-step explanation:
The set of chemical reactions that happen in living organisms to maintain life is called metabolism. Metabolism encompasses both the breakdown of molecules to release energy, known as catabolism, and the synthesis of new molecules that living systems require, known as anabolism. The thousands of biochemical reactions that constitute metabolism are either exothermic, releasing heat, or endothermic, absorbing heat, and are vital for the cell's survival and proper functioning.
These biochemical reactions are a part of a complex chemistry necessary for life's functions and include both energy-generating and energy-consuming processes. Bioenergetics is a term scientists use to describe the energy flow through living systems, illustrating how cells manage energy through various stepwise chemical reactions. Overall, metabolism is the total sum of all these reactions, ensuring that life sustains by replenishing energy and building necessary components within cells.