Matter and Energy Flow

B.12(C) analyze the flow of matter and energy through trophic levels using various models, including food chains, food webs, and ecological pyramids FOR LEAD INTO: E.7(B) calculate birth rates and exponential growth of populations

​Understanding Energy Flow

​EQ: How does energy flow from the sun through all living things?

Energy moves from the bottom to the top of an energy pyramid up the trophic levels.

• 90% of energy is lost as heat.

• 10% of energy moves up.

• You can move the decimal for each level to calculate.

  • i.e. 1000-->100-->10-->1

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​Energy pyramids

Carbon doesn't just cycle through photosynthesis and respiration.

It also cycles through:

• CO₂ emissions from factories to the atmosphere

• Death of organisms to soil

• Fossil fuels buried underground

Carbon Cycle

Nitrogen goes into the atmosphere by...

• Denitrifying bacteria

• Water cycle

Nitrogen is fixed into the soil by...

• Nitrogen-fixing bacteria

• Plant and animal decay by decomposers

• Lightning

• Water cycle

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Nitrogen Cycle