IE 116 1st Edition Lecture 2 Outline of Last Lecture I. Syllabus readingOutline of Current Lecture II. Plant Biology/Evolution/DiversityA. TimelineB. PhotosynthesisC. MetabolismIII. Plant Interactions with AnimalsA. Dispersal/Sexual PartnersB. DefenseC. Why are Chili Peppers Hot?IV. Current LectureII. Plant Biology/Evolution/DiversityA. Timeline- 500+ million years ago: Algae. No leaves or roots. Very little lignin (Fibers).o Uses Chlorophyll.o Includes Seaweed- 500+ million years ago: Moss. Bryophytes: Non vascular, no flower, no fruit.- 420+ million years ago: Ferns. Beginning of vascular, larger, structured, pre-seed.o Reproduce with spore pockets.- 380ish million years ago: Conifers. Gymnosperms = seeds fall and fly in wind.o Naked seedso Must be pollenated- 140-250ish million years ago: Fllowering Plants. Angiosperms = seed in a fruito With digestive durability of seeds, allowed ridiculous amounts of movement and diversity. Useful words. o Monocots: One nutrient storage area (Lilly/Orchids)o Dicots: Two nutrient storage area (Buttercup/Rose/Aster)B. Photosynthesis- It is an engine for plant metabolism.o CO2 + H2O + Light = Sugars + OxygenC. Metabolism- Primary Metaboliteso Directly involved in growth, development, or reproduction. Necessary to survival.o Celluloses/Lignin Fiberso Chlorophyll Light harvesting- Secondary Metabolites - MOST INPORTANT PART OF TODAYS LECTURE. It’s what we will be focusing on!o Produced by plants, attract pollinators, used as deterrents, and for defense.o Not immediately necessary.III. Plant Interactions with AnimalsA. Dispersal/Sexual PartnersPlants don’t move. This can make it difficult to find sexual partners. Thus Pollen- Wind dispersal of Pollen: Needs a lot of pollen. Falls off rapidly with distance.- Animal dispersal: Attractive odors, rewards (nectar), attractive colors.- Barb dispersal: attach to animals (or you when you’re hiking) and get moved that way.B. Defense- Use secondary metabolites: Toxins digestion inhibitors, antimicrobial, etc. o Includes uses for humans: caffeine, morphine, cocaine, etc.C. Why are Chili Peppers Hot?- Active ingredient: Capsaicinso Don’t do actual damage, simply trick cells into thinking they’ve been exposed to heat.- PARADOX! Chilies are hard to pollenate. So why hot?o Dispersal! Doesn’t want rodents dispersing close by. Wants BIRDS dispersing far.o Defense! Capsaicin is anti-fungal. Reduces the risk of infectiono Human Selection! Chilies are grown and bread for heat. Survival!- Bio explanation: Why eat something so hot?o Anti-fungalo Stimulationo Learned! Other animals will not gain a taste, but humans will. o (Benign
View Full Document
Unlocking...