Lecture 16: Secondary Metabolites (PNPs) - 11/6

Question 1

PNP (plant natural product) metabolism

Answer 1

Produces molecules that don’t appear to directly participate in the growth, development, or survival of the plant

Question 2

What is the benefit of PNP metabolism?

Answer 2

It generally increases fitness because it influences ecological interactions between the plant and other organisms

Question 3

What are the 3 main groups of PNPs?

Answer 3

Terpenoids, phenolics, and alkaloids

Question 4

Which parts of primary metabolism produce precursors for secondary metabolism?

Answer 4

PPP (pentose phosphate pathway), glycolysis, and the Krebs cycle

Question 5

Terpenoids

Answer 5

Derived from isoprene (5-carbon unit). Mostly multicyclic C structures with oxygen-containing functional groups

Examples of terpenes are carotenoids and menthol

Question 6

What are carotenoids? What do they do?

Answer 6

Photosynthetic pigments that also act as antioxidants (removes potentially damaging oxidizing agents).

These pigments also help give color to flowers and are the precursors to some plant hormones and volatile compounds (for scent, aroma)

Question 7

Phenolics

Answer 7

Molecules containing phenol groups

Question 8

Examples of phenolics

Answer 8

Lignin - mechanical strength and support in cell walls
Tannins - feeding deterrents
Flavonoids - UV filters

Question 9

Alkaloids

Answer 9

Nitrogen-containing molecules mostly synthesized from amino acids. Usually feeding deterrents and toxic to insects and other animals

Question 10

Examples of alkaloids

Answer 10

Morphine, cocaine, nicotine, caffeine, cannabis