Expansion of the Shikimate Pathway in Terrestrial Plants

The ultraviolet part of solar radiation is capable of promoting not only the formation but also the cleavage of chemical bonds. Hence the organic compounds 

The most conspicuous chemical difference between aquatic protists and terrestrial plants lies in the exploitation of the shikimate pathway. In all forms of algae, this is limited to the production of phenylalanine and tyrosine, already incorporated into proteins since primitive bacteria, and of derivatives of a few other pretyrosine molecules (Figs. 3.3 and 3.4). Only with the primitive tracheophytes, as 

Apart from UV radiation, there exist other phenomena in an aerial environment that require adaptation of plant life one concerns the relatively low humidity, and another the feeding pressure of herbivores. As in all chemical phenomena at the water/land interface, cinnamates are involved. Resistance to desiccation is provided by the water-impervious coating with waxes containing cutin in the aerial parts and suberin in the underground parts and at wound surfaces. Both 

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