The unique role of carbon in biochemistry

Case study 10.3 ) The unique role of carbon in biochemistry 

Now we can take stock of our knowledge of chemical bonding and continue the discussion in Section 9.12 of the properties of carbon that make it uniquely suitable for building complex biological structures. 

Among the elements of Period 2, carbon has an intermediate electronegativity, so it can form covalent bonds with many other elements, such as hydrogen, nitrogen, oxygen, sulfur, and, more importantly, other carbon atoms. Furthermore, because it has four valence electrons, carbon atoms can form chains and 

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