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	How does pollution flow through a water cycle? - chemicals that can dissolve into runoff water, pollutants like pesticides, fertilizers with chemicals

How does carbon move in a cycle? -  present in atmosphere by burning fossil fuels, released out of soil & people breathing. plants absorb it & goes back to soil. animal waste & decay releases it back into soil. when carbon collects in the soil = fossil fuels.

3 things that make the tropical rainforest unique: high amount of rainfall each year, low nutrients in the soil, dense forest

How does nitrogen move in a cycle? 80% atmosphere. rainfall, legumes, & fertilizer give it to the soil. humans & animals get it from foods, fixation through bacteria = turns it into a usable form.

What would the world look like without bacteria? 
no fixation: no nitrogen cycle - plants need it for growth 
no digestion: bacteria lives in stomachs
no decomposition: breaking down dead material

In terms of energy, why are there fewer top level predators than lower level consumers?  less energy - 10%,  gets transferred to top level producers 

Discuss three differences between the tropical rainforest & the African Savannah:
soil & nutrient level is less in rainforest
rainforest is more biodiverse
climate is different
less rain in savannah
vegetation & trees & grasses are different

draw a typical graph of a new species entering an area and then becoming a stable population

what is the difference between threatened, endangered, and extinct? & give example
threatened: a species that is starting to decline in numbers - coral, bald eagle
endangered: just a few left - snow leopards, panda
extinct: wiped out - dinosaurs

what is an example of how scientists measure biodiversity? sympson index of biodiversity, 10x10 piece of land divide number of species by total amount of species.