Senior Thesis Part I: Introduction to Secondary Metabolites in
Plants. In a dangerous situation or in times of sickness, humans
and animals have ways of avoiding damage: physically escaping a
predator and activation of white blood cells, among others.
Plants, however, have no motile appendages to flee danger and no
immune system to protect against pathogens1. Herbivorous
tetrapods began feeding on plants as early as the late
Coniferous period —about 300 million years ago2— and viruses
existed long before that. When angiosperms began to diversify,
such selection pressures necessitated the evolution of defense
mechanisms such as armor (like thorns, waxes, and
resins)3.However, herbivores have ways of overcoming mechanical
defenses: tough skin to protect against thorns, for example.
There became a need for a more efficient secondary defense:
secondary metabolites. By definition, a secondary metabolite is
any organic compound not used in the growth or reproduction of a
plant. For years, these were though of as ‘w