The sum of all biosynthetic reactions in a cell is known as

Answer: Anabolism

Explanation:

Anabolism refers only to all the metabolic reactions occuring in the cell that results in the formation of synthesis of substances required for proper functioning of the cell.

Examples include synthesis of biotin, glucose, lipids etc.

Anabolism is clearly different from catabolism, which does the exact opposite, as it concerns the breakdown or degradation of substances within the cell.