TOPIC: EcologyAIM: How are materials cycled through the environment?
Water
Cycle
• Evaporation (L G)
• Condensation (G L)
• Transpiration (liquid evap from leaves)
• Precipitation (rain…)
Precipitation Evaporation and Transpiration
Condensation
Carbon &
Oxygen
Cycle
• Involves photosynthesis & respiration
Cellular RespirationPhotosynthesis
carbon dioxide
oxygen
Nitrogen
Cycle
• Transfer of N from air to soil, to living things & back to air
Nitrogen Cycle
Nitrogen-fixing bacteriaNitrogen-fixing bacteria convert nitrogen gas to nitrates
Animals eat plants (produce nitrogenous wastes = urea & ammonia)
Plants use nitrates for protein synthesis
DecomposersDecomposers break down nitrogenous wastes and dead plants and animals release ammonia into soil
Nitrifying bacteriaNitrifying bacteria convert ammonia into nitrates
Plants use the nitrates ORDenitrifying bacteriaDenitrifying bacteria converts nitrates to nitrogen gas