Nutrients are essential elements or chemicals that support the growth, maintenance, and overall health of living organisms. They are required in varying amounts by different organisms, and their deficiency or excess can lead to various physiological and metabolic disorders. The most common nutrients needed by living organisms include macronutrients like carbon, nitrogen, phosphorus, sulfur, and potassium, as well as micronutrients such as iron, zinc, and copper.

Carbon is the primary constituent of organic compounds like carbohydrates, lipids, and proteins, which are vital for energy production, growth, and repair. Nitrogen is necessary for the formation of nucleic acids, amino acids, and proteins, which are essential for the structural and functional integrity of cells. Phosphorus is a component of ATP, DNA, and cell membranes and plays a critical role in energy metabolism, bone formation, and cell signaling.

Other essential nutrients include micronutrients like iron, which is involved in oxygen transport and metabolism, and zinc, which plays a role in immune function and wound healing. In summary, nutrients are fundamental components of life, and their proper intake and balance are essential for optimal health and well-being.