1. Lab 4. Overview  Instructor collects lab. 3 write ups and checks pre-labs. in lab notebook  Discussion of graded plant density write up.  Overview of Community Energy Flow, Soil, & Microorganism Colonies.  Soil composition determination  Plant pigment chromatography - Complete and turn in in-class exercise  Microbial species richness data  Soil animals  Exercise due in Lab 5 discuss. & questions

2. Communities  Community = A group of SPECIES living in the same area that have the potential for interaction.  Species Richness = number of SPECIES in a given area (community).

3.  Photosynthesis captures light energy in the molecule glucose. carbon dioxide (6 CO 2 ) + water (6 H 2 O) + light → glucose (C 6 H 12 O 6 ) + oxygen (6 O 2 ). Photosynthesis = primary production  Most organisms (including plants) break down glucose to get usable energy. Glycolysis & Cellular Respiration glucose (C 6 H 12 O 6 ) + oxygen (6 O 2 ) → carbon dioxide (6 CO 2 ) + water (6 H 2 O) + 36 ATP biotic energy Energy in Communities

4. Plant Photosynthesis & Respiration 6 CO 2 6 H 2 O 6 O 2 C 6 H 12 O 6 (energy) light (energy) photo- synthesis 32 ATP (energy used by plant) extra glucose (energy) used for structure as cellulose extra glucose (energy) stored as starch glycolysis & respiration other organisms can get glucose (energy) from eating starch &/or cellulose

5. Chlorophyll & Chromatography  Chlorophyll = large molecule that traps violet/blue & orange/red light as part of photosynthesis (reflects green/yellow)  Chromatography = method to separate molecules using a solvent and paper. We will use use chromatography to separate chlorophyll and other plant pigments.

6. Soil  Abiotic Soil Components = small pieces of “rock” (smaller) clay—silt—sand—gravel (larger)  Biotic Soil Components = small decomposing plants = organic material  Particle size and organic material affect soil nutrients, water retention, and permeability.  Water & nutrient availability often limit primary production by plants. sand silt clay

7. Soil Composition Determination

8. Microorganism Colonies  Microbial Colony = a cluster of bacteria or fungi on solid nutrient medium; the descendants of a single bacterium or fungal spore.  Microorganisms often differentiated based on colony characteristics.

9. Microbial Colonies

10. Today’s Activity Reminders  READ the instructions (  ) in the manual.  Mix the hell out of the soil. We’re testing in test tubes which requires a greater amount of agitation to mix. Don’t disturb once mixed and your first line is drawn on the outside of the test tube.  Work quickly with the acetone when putting plant pigment on the paper. It evaporates fast. Don’t inhale the chromatog. solvent.  Do not open the microbial plates. Leave the Parafilm around the edges.