Metabolism is the sum of all chemical processes that occur within living organisms to maintain life. It involves converting food and drinks into energy and building blocks for the body. Think of it as the body's internal chemistry lab, constantly working to keep us alive and functioning.
新陈代谢包括两种主要的过程。分解代谢是将复杂分子分解为简单分子的过程，在这个过程中会释放能量。合成代谢则相反，它将简单分子合成为复杂分子，需要消耗能量。这两个过程协同工作，维持生物体内能量和物质的平衡。
Cellular respiration is a key metabolic process where glucose and oxygen are converted into carbon dioxide, water, and ATP energy. This process occurs in three main stages: glycolysis in the cytoplasm, the Krebs cycle in the mitochondria, and the electron transport chain. One glucose molecule can produce thirty-six to thirty-eight ATP molecules, providing energy for cellular activities.
Several factors influence metabolic rate. Age is a major factor - metabolism typically slows down as we get older. Body size also matters, as larger bodies require more energy to maintain basic functions. Physical activity significantly increases metabolic rate, while temperature affects enzyme activity. Hormones, especially from the thyroid gland, play a crucial role in controlling overall metabolic rate.
To summarize what we have learned about metabolism: It is the sum of all chemical processes that maintain life in organisms. Metabolism includes both catabolism, which breaks down molecules, and anabolism, which builds them up. Cellular respiration is a key process that converts glucose into ATP energy. Various factors affect metabolic rate, and understanding metabolism helps us optimize our health and energy levels.