1. Key Concept: Carbon Cycle
Goals: Students will be able to …
Trace the pathway of a carbon atom through
living and nonliving components of an
ecosystem, explaining both the processes and
types of organisms involved.

2. Carbon Cycle Pre-test

3. Pre-test
Which of the following substances has mass? Answer yes or no in the blank to the left.
H20 vapor _______
CO2 _______
Glucose (C6H12O6) _______
O2 _______

4. Student Responses (n=171)

5. Pre-test What are the different pathways that carbon can
take once it is inside a plant? select as many as apply
a. it can exit the plant as CO2
b. it can become part of the plant’s cell walls, protein, fat, DNA
c. it can be consumed by an insect feeding on the plant and
become part of the insect’s body
d. as a plant decomposes in the soil, carbon can exit the soil
as CO2

6. Student Responses (n=171)

7. Pre-test The majority of the actual weight (dry biomass) gained by
plants as they progress from seed to adult plant comes from
which of the following substances?
a. molecules in the air that enter through the leaves
b. particle substances in the soil taken up by the roots
c. substances dissolved in water that are taken up by roots
d. energy from the sun

8. Student Responses (n=171)

9. Instructional Design Lecture: food chains and webs (15 min)
Lecture: energy flow / matter cycling (80 min)
Matter / conservation of matter
Energy / types of energy
Laws of thermodynamics
Efficiency of energy transfer
Biogeochemical Cycles- biological & geological forms and processes

10. Formative Assessment
Explain this statement: Energy flows through an ecosystem. Matter cycles within an ecosystem.
Discuss in your group - submit one answer per group.

11. In-class Group Activity
1. Draw a food chain based on the diagram of the carbon cycle in Figure Include the decomposers. Label each trophic level.
2. Incoming radiation from the sun is 1,7000,000 kcals. Based on how energy flows through ecosystems, calculate the amount of kcals available for each trophic level.
3. On the diagram, show how and in what form (use arrows) energy is lost from each trophic level.
4. On the diagram, indicate in what form carbon moves into and out of each trophic level and the biological process that enables carbon movement to occur.

12. Radish Experiment Experimental Setup:
Weighed out 3 batches of radish seeds each weighing 1.5 g.
Experimental treatments:
1. Seeds placed on moistened paper towels in LIGHT
2. Seeds placed on moistened paper towels in DARK
3. Seeds not moistened (left DRY) placed in light

13. Radish Experiment In-class group activity:
Develop a testable hypothesis for your group’s experiment.
Define the dependent and independent variables in your hypothesis.
Design a method to measure primary productivity for your experiment.
Predict the results.

14. Radish Experiment
After 2 weeks, all plant material was dried in an oven overnight (no water left) and plant biomass was measured in grams.

15. Processing Radish Experiment (week 7)
1.46 g g g
Formative Assessment: Write an explanation of the results.

16. The Grandma Johnson Problem
Hypothetical Scenario: Grandma Johnson had very
sentimental feelings toward Johnson Canyon, Utah where she
and her late husband had honeymooned long ago. Her feelings
toward this spot were such that upon her death she
requested to be buried under a creosote bush overlooking the
canyon. She loved the idea that she'd become part of the
wonderful wilderness and live on through the wildlife that
lived there. Think to yourself and begin to trace the path of a
carbon atom from Grandma Johnson's (GJ) remains to where
it could become part of a coyote (NOTE: the coyote WILL
NOT dig up Grandma and consume any of her remains). What
fundamental pathways and processes of biology will be
involved in the transit of GJ's carbon atoms to that of the
wild coyote in Utah?

17. Task: Create a concept map that illustrates your understanding of the relationship between these 10 concepts in the context of the Grandma Johnson problem. You may add up to 5 extra concepts if you need them to explain the problem more clearly.
photosynthesis
respiration
carbon cycle
decomposers
primary producers
consumers
carbon dioxide
glucose
energy
oxygen
1. Work on the problem individually first, save it in CTOOLS, and print a hard copy Work on the problem with a partner. Both of you can retrieve your concept maps, discuss, revise and produce the best final map to which both of you have contributed Submit all three maps - yours, your partner's and the FINAL MAP you completed together - Please put the final map on top, with both of your names. Staple them together (5 pts off if not stapled).

18. Summative Assessments
Analogous questions from pre-test
The final exam was optional; 72 of 182 students chose not to take the final
The following data are from the 110 who took the final

19. Summative Assessment (final exam)
Which of the following substances has mass? Answer yes or no in the blank to the left.
H20 vapor _______
CO2 _______
Glucose (C6H12O6) _______
O2 _______

20. Student Responses (n=110)

21. Summative Assessment (final exam)
What are the different pathways that carbon can
take once it is inside a plant?
a. it can exit the plant as CO2
b. it can become part of the plant’s cell walls, protein, fat, DNA
c. it can be consumed by an insect feeding on the plant and
become part of the insect’s body
d. as a plant decomposes in the soil, carbon can exit the soil
as CO2

22. Student Responses (n=171)

23. Summative Assessment (final exam)
The majority of the actual weight (dry biomass) gained by
plants as they progress from seed to adult plant comes from
which of the following substances?
a. molecules in the air that enter through the leaves
b. particle substances in the soil taken up by the roots
c. substances dissolved in water that are taken up by roots
d. energy from the sun

24. Student Responses (n=171)

25. Success!!
Students understand the carbon cycle.
Really??

26. Appropriate Assessment
Three questions on the final exam assessed student understanding of the concept that plants get carbon from CO2 in the atmosphere.

27. Multiple Choice
The majority of the actual weight (dry biomass) gained by
plants as they progress from seed to adult plant comes from
which of the following substances?
a. molecules in the air that enter through the leaves
b. particle substances in the soil taken up by the roots
c. substances dissolved in water that are taken up by roots
d. energy from the sun

28. Fill-in table

29. Spider Monkey Problem
Written response: Explain in detail the following:
Deep within a remote forest of Guatemala, the remains of a spider monkey were buried under an enormous mahogany tree. Although rare, jaguars have been spotted in this forest by local farmers. Use coherently written sentences and clearly labeled drawings to explain how a carbon atom in glucose contained within the muscle cells of the spider monkey might become part of a cell within the stomach lining of a jaguar. Provide a written description of the processes AND organisms the carbon atom must go through to cycle through the ecosystem. Include a clearly labeled drawing of the system. (Note: the jaguar does not dig up the monkey and eat the remains!)

30. Where do plants get carbon? (final exam)