Which type of reaction is associated with assembling substances?

The answer is B, which refers to anabolic reactions. Anabolic reactions are metabolic pathways that construct molecules from smaller units. These processes require energy and are vital for growth, repair, and the synthesis of complex molecules such as proteins, nucleic acids, and carbohydrates in living organisms.

Anabolic reactions include processes like protein synthesis, where amino acids are combined to form proteins, and photosynthesis, where carbon dioxide and water are converted into glucose and oxygen. These reactions play a crucial role in building cellular structures and maintaining the functions necessary for life.

The other types of reactions mentioned are characterized by different functions. Catabolic reactions, for instance, break down larger molecules into smaller components, releasing energy. Hydrolysis reactions involve the breaking of bonds through the addition of water, usually resulting in the breakdown of complex molecules. Oxidation reactions involve the loss of electrons or the addition of oxygen, which can be associated with energy release rather than the assembly of substances. Understanding these reactions is key to grasping how living organisms utilize energy and construct the necessary components for life.