The cellular process of synthesizing large molecules from smaller ones is defined as

anabolism

Explanation:

Anabolic processes are basically construction, growth or synthesis processes, in which large molecules are obtained from other smaller molecules.

Through anabolic processes, molecules that form new cells are obtained. During these construction processes, a large amount of energy is consumed, for example, through protein building reactions, from amino acids. Anabolism is the metabolic process responsible for the formation of cellular components, muscle tissues and, therefore, growth.