1.  Draw a food chain for a pond consisting of 4 or 5 organisms.  Label the different trophic levels.  With the other people on your table, turn your food chains into a food web on the mini whiteboard.

3.  Complete the summary questions on p66.  Do the ecological efficiency sheet.

4. Gross Productivity – Energy “fixed” by the producers in photosynthesis and stored as chemical energy in glucose. Net Productivity – Energy accumulated in producer biomass and available to consumers after energy losses from plant’s own metabolic reactions (heat/respiration) have been taken into account. Primary Productivity - Amount of plant biomass (crop) produced. Secondary Productivity – Amount of consumer biomass (tissue) produced.