Secondary Metabolites

Question 1

What are Secondary Metabolites

Answer 1

Carbon compounds have no role in growth and development but play an essential role in plant defense and structure.

Question 2

The basic class of Secondary Metabolites: Terpenoids

Answer 2

• 5 carbon chain
• Involved in hormone biosynthesis of gibberellins, brassinosteroids, and carotenoids.
• Biosynthesis happens in
  glandular trichomes
  secretory cavities in leaves
  flower petals
  Resin ducts
  -Pyrethroids: These occur in the leaves and flowers of daisies and are an effective natural insecticide.
  -Latex: Emulsion secreted in special phloem cells. Russian dandelions have high latex levels in their roots.
  -Artemisinin: effective antimalarial
  -Cannabis

Question 3

The basic class of Secondary Metabolites: Phenolics

Answer 3

-OH group of phenolic
-Involved in defense, durability, flower color, taste, and odor.
-Lignins: defense compounds,
antioxidants. Forms in walls of cells that form a secondary xylem.
-Flavonoids: anthocyanins (pigments dependent on soil pH/ High AI3+ in vacuole and pH gives blue, middle give purple, low gives pink, attracts pollinators) tennis(protection), isoflavonoids (defense/signaling)
-Coumarins involved in warfare of plants against animals, warfarin: synthetic used in rate poison.

Question 4

The basic class of Secondary Metabolites: Alkaloids

Question 5

Resin ducts

Answer 5

Secretion of resin containing turpentine from the holes made by burrowing beetles. Once evaporated, the resin solidifies and plugs the hole.

Aromatic resin:
Myrrh: resin of small, thorny tree species.

Frankincense: resin used in incense and perfumes

Agarwood: source of incense, Hydro-distillation process used to extract essential oils

Question 6

types of phenolics

Answer 6

Coffee beans
Cloves
Nutmeg
Cinnamon
Ginger
Red and Black peppers
Rose and other flowers
Vanilla

Question 7

Senescence

Answer 7

Controlled nutrient remobilization leads to cell death.
Influences include hormonal signals (e.g., ethylene, cytokinins) and environmental stressors (e.g., shading, and drought).
Key processes: chlorophyll breakdown, nutrient recycling, and involvement of autophagy.

Question 8

Sarin vs Atropine

Answer 8

Sarin’s action: inhibits acetylcholinesterase (AChE), causing acetylcholine buildup.
Atropine’s role: blocks muscarinic receptors to alleviate symptoms without addressing the root cause.