Which of the following elements is most abundant in cells?
Biological elemental composition reflects chemistry of water and carbon based macromolecules. Water, ~70% of cell mass, contributes two hydrogens per oxygen, while macromolecules proteins, nucleic acids, carbohydrates, lipids contain abundant oxygen in carbonyl, hydroxyl, carboxyl, phosphate and ether linkages. Consequently by wet mass oxygen is most abundant element constituting approximately 65% of human body, followed by carbon ~18% forming organic scaffold with tetravalency allowing complex polymers, hydrogen ~10% from water and hydrocarbon chains, nitrogen ~3% in peptide bonds and heteroc
Ref: Lehninger Principles of Biochemistry, 8th ed., Chapter 1: Elemental Composition of Cells.
