1. Biological Communities

2. Community Energy Energy enters biotic communities via photosynthesis
transferred between organisms in feeding
used for growth, energy via respiration

3. Food Webs
The biota of an ecosystem are tied together in complex networks – food webs - that reflect feeding relationships

4. Eco pyramids energy transfer numbers of organisms
A large base needed to support the levels above
amount of biomass

5. Energy transfer
Inefficient: only a small fraction of food converted to ATP
Where is the remainder?
~10%
stored in tissues (biomass)
waste products
Converted to heat (respiration)