Essential Idea:
Ecosystems require a continuous supply of energy
to fuel life processes and to replace energy lost as heat
Understandings:
- Most ecosystems rely on a supply of energy from sunlight
- Light energy is converted to chemical energy in carbon compounds by photosynthesis
- Chemical energy in carbon compounds flows through food chains by means of feeding
- Energy released from carbon compounds by respiration is used in living organisms and converted to heat
- Living organisms cannot convert heat to other forms of energy
- Heat is lost from ecosystems
- Energy losses between trophic levels restrict the length of food chains and the biomass of higher trophic levels
Skills:
- Quantitative representations of energy flow using pyramids of energy