PSI Barbering Practice Exam 2026 – 400 Free Practice Questions to Pass the Exam

The term that encompasses all chemical processes occurring in living organisms is metabolism. This includes all of the biochemical reactions that take place to maintain life, such as the breakdown of nutrients to extract energy (catabolism) and the synthesis of necessary compounds (anabolism). Metabolism is essential for growth, reproduction, and responding to environmental changes, acting as the foundation for energy transformation and the regulation of biological functions within the organism.

Homeostasis refers to an organism's ability to maintain stable internal conditions, which is a result of metabolic processes but not the entirety of them. Catabolism is specifically the part of metabolism that involves breaking down molecules, while photosynthesis is a specific process used by plants to convert sunlight into chemical energy, which is not comprehensive of all metabolic activities. Therefore, metabolism accurately describes the full range of chemical processes vital for sustaining life.