The correct answer is: B) supply energy, primarily in the form of ATP, for the cell's work
There are two main types of metabolic reactions:
1. Catabolic reactions (catabolism) are reactions of molecule breakage-macromolecules are broken down to basic units (monomers) and energy in the form of ATP is released. Formed monomers are used for the synthesis of new molecules or are released as waste.
2. Anabolic reactions (anabolism) are reactions of synthesis or building up of the macromomolecules. Anabolic reactions require energy, which means that are endergonic process and that energy is powered by catabolic reactions.