Lecture 1: Evolution and Natural History of Medicinal Plants Flashcards
Photosynthesizing plants appeared during the —— period
Silurian
First branching plant was called —–
Cooksonia
—— appeared slightly earlier than —–
Terrestrial fungi
functions of fungi
- they excrete digestive enzymes and absorb externally digested nutrients
- they also contributed to soil formation and facilitated plant growth
—- was the very first fungi ever identified
Tortutubus
Structure of fungi
they have a fruiting body and a large network of underground hyphae (the majority of the organism is underground)
The Devonian period
Domination of phototaxis
How to ID a flavonoid
6-3-6
Gallic acid is made of:
Gallic acid is the subunit in:
1) Phenol
2) Tannic acid
Aquatic plants vs. Terrestrial plants in terms of defence
Aquatic plants are not as chemically hazardous as terrestrial plants to the herbivores.
what is the goal of the release of arsenal compounds by plants?
to deter eating, discourage the growth of other seedlings, and inhibit soil bacteria and fungi.
plant’ s strategy against water loss:
developed a layer of epidermal cells coated by a waxy cuticle layer
plant’s strategy against UV radiation
water served as a filter for direct sunlight
- Flavonoid pigments: reflect UV wavelengths
Function of Tannins:
- They limit a plant’s palatability; accumulate in the bark of woody specifies.
- Can bind to digestive enzymes and interfere with digestion.
- Can also cause cancers in animals and people who are chronically exposed to tannins (continuous exposure).
Function of phytochemical
1) some have immediate deterrent effects
2) some regulate life cycles and development to affect future generations of herbivores
3) some interfere with brain activity and neural functions
4) due to their diverse, complex metabolic effects, they have been used as medicines since ancient times
