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How do carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur support life?

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Diagram illustrating Earth's environmental spheres, with labeled sections showing the geosphere (land and crust), biosphere (living things), atmosphere (air), and hydrosphere (water), each extending vertically from the Earth's surface. — Biosphere Earth's environment includes the atmosphere, the hydrosphere, the lithosphere, and the biosphere.

In the context of the biosphere, carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur are the six major elements that form the core protoplasm of all living organisms. These elements are essential for growth and the sustenance of life, often occurring in similar proportions across diverse life-forms.1

Carbon: As the basis of organic chemistry, carbon atoms form stable bonds with four other atoms, allowing for the construction of complex molecules like carbohydrates, proteins, and lipids.2
Hydrogen and Oxygen: These elements are critical for energy metabolism. In mitochondria, the controlled oxidation of hydrogen by oxygen releases energy used to synthesize ATP.3
Nitrogen: This element is fundamental to the structure of DNA, RNA, and amino acids, and it is a core component of chlorophyll and ATP.45
Phosphorus: Essential for cellular activity, phosphorus is a key component of DNA and ATP, and it provides structural support in bones and teeth as calcium phosphate.6
Sulfur: Sulfur atoms form disulfide bridges in proteins, which are crucial for maintaining the specific three-dimensional shapes required for biological activity and structural stability in tissues like keratin.78