1. nitrogen cycle dr shabeel pn www.hi-dentfinishingschool.blogspot.com

2. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - Which can be taken back up by plants and made into proteins Denitrifying bacteria use nitrates and release nitrogen into the air Lightning and the addition of fertlisers also adds nitrates to soil

3. 80 % of the atmosphere is made up of nitrogen gas N 2

4. nitrogen gas is very unreactive and very few organisms can extract it from the air

5. Nitrogen is essential for all organisms as it is needed to make proteins

8. Plants can easily make carbohydrates like sugars and starches

9. +

10. NO 3 - + nitrate ions need to be added to carbohydrates to make amino-acids

11. NO 3 - + nitrate ions need to be added to carbohydrates to make amino-acids Amino acid

12. Amino acid

13. Amino acid Amino acid

14. Amino acid Amino acid Amino acid

15. Amino acid Amino acid Amino acid Amino acid

16. Amino acid Amino acid Amino acid Amino acid Amino acid

17. Amino acid Amino acid Amino acid Amino acid Amino acid The amino-acids are joined together in chains to make polypeptides

18. But where does the nitrate come from?

19. But where does the nitrate come from?

20. But where does the nitrate come from? Certain bacteria are able to take atmospheric nitrogen and “fix” it into nitrate ions

21. N 2

22. N 2

23. N 2

24. N 2 NO 3 -

25. N 2 These nitrogen fixing bacteria are either free living in the soil... NO 3 -

26. These nitrogen fixing bacteria are either free living in the soil... Or live in special nodules in the roots of plants

28. These nitrogen fixing bacteria are either free living in the soil... Or live in special nodules in the roots of plants

29. These nitrogen fixing bacteria are either free living in the soil... Or live in special nodules in the roots of plants

30. These nitrogen fixing bacteria are either free living in the soil... Or live in special nodules in the roots of plants

31. These nitrogen fixing bacteria are either free living in the soil... Or live in special nodules in the roots of plants

32. NO 3 -

33. NO 3 - The nitrate in the soil or in the root nodules can then be used by the plant to make proteins

34. Bacteria also help to recycle the nitrogen that has been made into protein

36. After death...

38. And of course the production of waste compounds containing nitrogen

40. Bacteria break down these proteins and waste products to release ammonia NH 3

41. Bacteria break down these proteins and waste products to release ammonia NH 3

42. Bacteria break down these proteins and waste products to release ammonia NH 3 protein

43. Bacteria break down these proteins and waste products to release ammonia NH 3 protein

44. Bacteria break down these proteins and waste products to release ammonia NH 3 protein

45. Bacteria break down these proteins and waste products to release ammonia NH 3 protein NH 3

46. The ammonia is further broken down by Nitrifying bacteria to release nitrates NH 3

47. The ammonia is further broken down by Nitrifying bacteria to release nitrates NH 3 NO 3 -

48. Unfortunately some of the nitrates in the soil end up back as nitrogen in the atmosophere...

49. Nitrates

50. Nitrates

51. N 2 Nitrates Denitrifying bacteria use nitrates and release nitrogen into the air

52. Putting it all together into a cycle...

53. N 2

54. N 2

55. N 2

56. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates

57. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates

58. N 2 Nitrogen fixing bacteria in soil and nodules of plants NO 3 -

59. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 -

60. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 -

61. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 -

62. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating

63. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating

64. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay

65. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay

66. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay

67. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 -

68. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 -

69. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - Which can be taken back up by plants and made into proteins

70. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - Which can be taken back up by plants and made into proteins

71. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - Which can be taken back up by plants and made into proteins

72. N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - Which can be taken back up by plants and made into proteins Denitrifying bacteria use nitrates and release nitrogen into the air Lightning and the addition of fertlisers also adds nitrates to soil