1. Biology Today Third Edition Chapter 11 Plants to Feed the World Copyright © 2004 by Garland Science Eli Minkoff Pam Baker

2. Plants to Feed the World A.Plants Uses (food, etc) nutrition (photosynthesis; know equation) B.Economics Plants are producers Animals (and others) are consumers Fungi and bacteria are decomposers Energy flows through the economy Chemicals are recycled within the economy e.g., the nitrogen cycle

3. Plants to Feed the World C.Plant anatomy parts and functions vascular tissue water movement (osmosis, transport, transpiration) D.Increasing crop yield Fertilizer (benefits and dangers) Soil makeup and conservation Water distribution (hydroponics) Monocultures (benefits and dangers) Pests and controlling them Food pyramid and biomagnification GMO’sadvantages / disadvantages ? (genetically modified organisms -= GMO)

4. Plants Over 250,000 species 80,000 are edible by humans 30 major crops in the world 4 feed more than all others wheat rice corn potatoes Food

5. Plants Food (Drinks, spices) Fragrances Dyes Poisons Decorations Building material Medicines Fuel Paper

6. Plant Nutrition autotrophic photosynthesis (energy) sunlightCO 2 H2OH2OglucoseO2O2 +++

7. Sun supplies all of our energy Plants capture and store energy (autotrophic) Energy flow We eat plant material to get energy (heterotrophic) producers consumers primary, secondary, … Some organisms are absorptive heterotrophs decomposers

8. Fig. 11-1

9. Fig. 11-2

10. Fig. 11-3

11. Fig. 11-4

12. Fig. 11-5

13. Chemicals cycle Energy flow usplants C 6 H 12 O 6 O 2 H 2 O CO 2

14. Chemicals cycle Other chemical cycle too e.g., nitrogen amino acid, DNA, RNA

15. Chemicals cycle Plants need nitrogen too absorb nitrates and nitrites nitrogen-fixation convert N 2 from air to NH 3 nitrification convert NH 3 to NO 3 -,NO 2 -

16. Fig. 11-6

17. Fig. 11-8

18. Plant Anatomy Specialized plant parts: leaves roots stems flowers photosynthesis absorption transport reproduction vascular tissue xylem phloem water and minerals nutrients (sap)

19. Fig. 11-9

20. hypotonic Fig. 11-10

21. Increasing crop yields Fertilizer adds nutrients needed by plants to the soil Animal waste (manure) Composting Chemical fertilizer disease & run-off

22. Fig. 11-13

23. What do plants need to grow ? water soil

24. Soil Loose material weathered rock organic material

25. Soil types parent rock climate groundwater activity of living organisms

26. topsoil made slowly (1 inch/200-1000 years) lost to erosion “non-renewable” don’t poison it or loose it

27. Plants to Feed the World A.Plants Uses (food, etc) nutrition (photosynthesis; know equation) B.Economics Plants are producers Animals (and others) are consumers Fungi and bacteria are decomposers Energy flows through the economy Chemicals are recycled within the economy e.g., the nitrogen cycle

28. Plants to Feed the World C.Plant anatomy parts and functions vascular tissue water movement (osmosis, transport, transpiration) D.Increasing crop yield Fertilizer (benefits and dangers) Soil makeup and conservation Water distribution (hydroponics) Monocultures (benefits and dangers) Pests and controlling them Food pyramid and biomagnification GMO’sadvantages / disadvantages ? (genetically modified organisms -= GMO)

29. Water 90% lost to transpiration plants need it: photosynthesis transport turgor pressure

30. Irrigation supplying water to crops expensive ? Increasing crop yields

31. What do plants need to grow ? wateryes soilno Hydroponics growing crops without soil

32. expensive construction maintenance monoculture “inside” controlled climate protected no tilling more control Fig. 11-15

33. Monocultures single species rapid spread of disease damage by pests depletion of soil

34. Figure 11.16 (1)

35. Figure 11.16 (2)

36. Controlling pests 30% of many crops are destroyed insects (adult and/or larvae) rodents fungi protect with pesticides (kills pests) Increasing crop yields

37. Controlling pests ideal pesticide kill only target pest no effect on non-targets avoid devel. of resistance strains breakdown to harmless substances ideal pesticide does not exist Increasing crop yields

38. DDT kills lots of insects sprayed on soldiers to kill lice used on crops to kill pests (more food) sprayed on water to kill mosquitoes (less disease) Increasing crop yields Controlling pests

39. DDT expensive kills non-target species DDT-resistance pollute drinking water biomagnification food pyramid Controlling pests

40. Width shows biomass p r o d u c e r s must be on bottom they can’t pass on all their energy to next level primary consumer secondary consumer

41. Figure 11.17

42. Controlling pests biomagnification some chemicals get concentrated in tissues of the body

43. Figure 11.18

44. many pesticides interfere with the nervous system of the pest Controlling pests may damage our nervous system as well

45. Controlling pests Integrated pest control monitor pest levels Increasing crop yields

46. Figure 11.19a

47. Controlling pests Integrated pest control monitor pest levels pheremones Increasing crop yields

48. Figure 11.19b

49. Controlling pests Integrated pest control monitor pest levels pheremones predator species Increasing crop yields

50. Figure 11.19d ? safe

51. Figure 11.19d exotic species

52. Controlling pests Integrated pest control monitor pest levels pheremones predator species economic impact... Increasing crop yields cost/ benefit

53. Increasing crop yields Artificial selection “These breeders chose individuals of the species that best exemplified the trait they desired. They allowed these individuals to mate, while preventing mating between individuals that did not have the desired trait.”BT3 pg. 397

54. Figure 11.20

55. Increasing crop yields Green Revolution Export better strains to poor countries Better yields… … we are no better off population growth sustainability See quote page 398, BT3

56. Increasing crop yields Genetic engineering (GMO’s) transgenic plants nutritional value (protein, starch) pest resistance herbicide resistance shelf life

57. Increasing crop yields Genetic engineering (GMO’s) transgenic plants molecular farming tobacco have plant make “products” “blue genes” blue pigment gene into cottons plants

58. Increasing crop yields Genetic engineering (GMO’s) transgenic plants risksbiological ? concernsethical ?