The study of the elements of life reveals that only a small subset of the known elements in the universe is essential for living organisms. The periodic table organizes all known elements based on their chemical properties, but among these, only a few are crucial for life. Notably, 97% of the mass of most living organisms is composed of just six elements: carbon (C), hydrogen (H), nitrogen (N), oxygen (O), phosphorus (P), and sulfur (S). A helpful mnemonic to remember these elements is "CHANOPS," which represents the first letter of each element.
These six elements are referred to as bulk elements due to their abundance in living organisms. In contrast, trace elements are also necessary for life but are required in much smaller amounts. While the bulk elements are found in significant quantities, trace elements are present in minimal concentrations. These trace elements, highlighted in yellow in the periodic table, play vital roles in various biological processes, although it is not necessary to memorize all of them.
Understanding the distinction between bulk and trace elements is essential for grasping the foundational concepts of biochemistry and the composition of living organisms. As you continue your studies, keep in mind the importance of CHANOPS and the role of trace elements in sustaining life.