What are the two phases of cell metabolism?

The two phases of cell metabolism are anabolism and catabolism.

Anabolism refers to the constructive processes through which cells synthesize complex molecules from simpler ones. This phase is crucial for growth, repairing tissues, and storing energy, as it involves building up cellular components like proteins, nucleic acids, and polysaccharides.

Catabolism, on the other hand, is the breakdown phase where larger organic molecules are broken down into smaller units. This process releases energy that the cell can use for various functions, including the anabolic reactions. Together, these two phases of metabolism ensure that cells can efficiently manage energy and materials, maintaining the balance necessary for healthy functioning.

The other options do not correctly represent the phases of cell metabolism, as excretion and absorption are processes related to the removal and uptake of substances, fermentation and respiration are more specific energy-producing pathways, and activation and deactivation do not denote distinct phases of metabolism.