1. Ecology Grid-In Practice Questions Matter and energy cycles are likely candidates for at least one of the six grid in questions on May’s exam.

2. Determine the amount of carbon that reaches the ocean surface from marine biota. Follow the arrows. 50 GT enters the biota in the ocean. Of that, 6 GT ends up in dissolved organic carbon; 4 GT ends up in the deep ocean. This means 10 GT does not cycle back to the surface. 50 GT – 10 GT = 40 GT

3. Phytoplankton

5. Generalized Oceanic Ecosystem

6. How much carbon (in g/m 2 ) from zooplankton is used by decomposers? Give your answer to the nearest whole number. 160 g/m 2 taken in by phytoplankton; 60 g/m 2 lost by zooplankton by respiration; 8 g/m 2 lost by zooplankton by predation. 160 – 60 - 8 = 92 g/m 2

7. After seven days of growth, a plant’s weight was 14.3 grams. The percent biomass of that plant was determined to be 23.1%. What amount of energy (in kcal) is stored in the plant, if the amount of stored energy = (g biomass) x 4.35 kcal? 14.3 g wet mass * 0.231 = 3.30 g dry mass (biomass) 3.30 g biomass * 4.35 kcal/g biomass = 14.4 kcal

8. Energy taken in by producers: 20,950 kcal Energy taken in by carnivores: 328 kcal Carnivore fraction: (328/20,950)*100 = 1.57% (1.6%)