Biological Role and Toxicity
The first element in group 14, carbon, is uniquely important in the chemistry of life. It is a key structural constituent of the many classes of compound which make up biological systems, such as lipids, carbohydrates and proteins. Whilst these compounds also contain other elements such as oxygen and hydrogen, it is the ability of carbon to form stable chains of multiple carbon-carbon bonds that is crucial in allowing such an enormous diversity of different biological molecules to exist. The oxidation and reduction of carbon to different oxidation states is the fundamental basis of the reactions that constitute biochemistry.
In contrast, the other elements of the group are largely absent from biochemistry, with toxicity to most organisms increasing down the group. Lead in particular is a serious environmental poison.
Read more about this topic: Carbon Group
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