1. Cycles in Ecosystems Oxygen Water Carbon Nitrogen

2. Eco Column Lab

5. Oxygen Cycle

8. Crash Course: Water and Carbon Cycles

9. The Carbon Cycle

10. The most common elements found in living things: The most common elements found in living things: Oxygen (O) Oxygen (O) Hydrogen (H) Hydrogen (H) Carbon (C) Carbon (C) Nitrogen (N) Nitrogen (N) Calcium (Ca) Calcium (Ca) Phosphorus (P) Phosphorus (P)

11. Carbon is the key element in living things. Each carbon atom can bond to four other atoms Each carbon atom can bond to four other atoms Carbon atoms can bond to other carbon atoms Carbon atoms can bond to other carbon atoms

12. Carbon atoms can be used to build thousands of different compounds

13. About 70% of all compounds contain carbon About 70% of all compounds contain carbon Compounds that contain carbon are called organic compounds: Compounds that contain carbon are called organic compounds: CoalGraphiteOil CO 2 DiamondsLimestone WoodPlasticNylon Organic chemistry: chemistry of carbon Organic chemistry: chemistry of carbon

14. Inorganic compounds don’t contain carbon: Water (H 2 O) Water (H 2 O) Glass (SiO 2 ) Glass (SiO 2 ) Metals (Fe, Al, Cu, Au) Metals (Fe, Al, Cu, Au) Oxygen gas (O 2 ) Oxygen gas (O 2 )

15. On Earth, carbon exists in five main places (“carbon pools”): 1. Earth’s crust (limestone and oil) 99.9% of all Earth’s carbon 99.9% of all Earth’s carbon 2. Oceans 3. Soil (humus) 4. Atmosphere (CO 2 ) 5. Living things

16. In the carbon cycle, carbon atoms move between these five “pools”

17. Producers (plants) take carbon from the atmosphere during photosynthesis

18. Photosynthesis: CO 2 + H 2 O + energy  C 6 H 12 O 6 + O 2 Carbon dioxide from air Water from soil SunlightGlucose Oxygen

19. Animals take in carbon by eating plants Energy is released from glucose during Respiration: Energy is released from glucose during Respiration: C 6 H 12 O 6 + O 2  CO 2 + H 2 O + energy Respiration is the opposite of photosynthesis Respiration is the opposite of photosynthesis

20. Respiration

21. Dead plants and animals return their carbon to the soil or atmosphere when they decompose

22. Humans add carbon to the atmosphere by burning fossil fuels

23. Carbon Cycle (draw in your notes) Crash Course: Carbon is a Tramp 1:50 – 5:10

24. The Nitrogen Cycle

25. Nitrogen (N) occurs in the environment in many forms Nitrogen gas (N 2 ) makes up about 78% of the air around us

26. Plants and animals need nitrogen, but can’t get it directly from the air Plants use nitrates (NO 3 ) Animals use amino acids (NH 3 )

27. Certain bacteria are able to turn nitrogen gas into nitrate: nitrogen fixation Nitrogen-fixing bacteria live in nodules on the roots of some plants (ex. Legumes: beans, clover)

28. Other bacteria turn nitrates back into nitrogen gas

30. In aquariums, nitrates build up and turn into ammonia, which is toxic to animals

31. Aquarium filters use helpful bacteria to remove excess nitrates and ammonia

32. Humans affect the nitrogen cycle by using large amounts of fertilizers

33. Draw one of the following illustrations of the nitrogen cycle in your notes

34. Crash Course: Nitrogen Cycle