1. Carbon: Transformations in Matter and Energy Environmental Literacy Project Michigan State University Decomposers Unit Activity 2.2 Observing Bread Molding

2. Investigation Tools What mass changes will we observe? What changes in BTB will we observe? 2

3. Day 1 Instructions (Day 1) Find the Mass of Your Bread and Mold. ☐ Collect your labeled Petri dish with bread and mold, a digital balance, and your worksheet from the Pre-Lesson. ☐ Look on your worksheet from your Pre-Lesson and find the beginning mass of your Petri dish and bread from 7 days ago. Write the mass on your 2.2 Observing Bread Molding Worksheet in the table where it says “Mass of Petri dish and bread and mold before (7 days ago).” ☐ Turn on your digital scale until it reads 0.00g. Place the entire Petri dish with the lid onto the scale. Record the final mass of your Petri dish where it says “End Mass (after 7 days)” in the table below. Note: DO NOT open the lid—classmates may have allergies to bread mold. ☐ Record the final mass of your Petri dish, bread, and mold on your 2.2 Observing Bread Molding Worksheet in the table where it says “Mass of Petri dish and bread and mold after (today).” (Day 1) Set up the BTB Investigation. ☐ Gather a large, sealable container (1 per group). ☐ Stack all four of your group’s Petri dishes in the container. ☐ Put an open Petri dish with BTB in it next to the moldy bread inside the container. ☐ Record the color of the BTB on your 2.2 Observing Bread Molding Worksheet in the table where it says “Color of BTB before.” ☐ Seal the container and wait 24 hours for results. 3

4. Possible BTB Colors 3

5. Comparing Group Results Results for mass changes What patterns are there in measurements made by all the groups? Do the patterns match your predictions? Results for BTB changes What patterns are there in observations made by all the groups? Do the patterns match your predictions? 4

6. BTB Results for Ms. Drayton’s Class Day 1Day 2 start BTB color end BTB color blueyellow blueyellow blueyellow blueyellow blueyellow blueyellow How do your results compare with the results from Ms. Drayton’s Class? 5

7. Mass Results for Ms. Drayton’s Class How do your results compare with Ms. Drayton’s class results? Initial mass bread and mold in Petri dish (g) Final mass after 7 days (g) Change in mass after 1 week (g) 39.5037.60-1.90 23.5120.75-2.76 35.5731.38-4.19 29.2625.38-3.88 31.6730.37-1.30 32.1831.36-0.82 33.2731.13-2.14 30.8628.95-1.91 Average change in weight = -2.63 6