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