Carbon Cycling

1. At approximately 60 hours, seedlings begin to emerge from the soil. Describe the trend in the graph from 0-60 hours. Does this trend support or refute the idea of "Plants use Oxygen"

2. At approximately 137 hours the levels of CO2 are at a peak. From 137 hrs to 216 hrs, describe the relationship amongst the  CO2 levels,  O2  levels and light.  

3. A student noticed several peaks in the  CO2 levels at 137 h, 161 h, 185 h and 209 h (24 hour cycles). However, she found that the peaks were lower in  CO2  concentration each day. Propose a claim regarding where why the  peak levels of CO2 would be dropping.

4. On the graph of data four clear peaks are show at the times above. Suppose the data collection were to continue for another 5 days. Sketch on your graph the peaks of these 5 days. Support your claim based on 

The diagram shows the movement of carbon between different parts of the Earth's system. In the image, the numbers in yellow represent the natural fluxes, the red numbers are the human contributions in gigatons of carbon per year (GtC/yr), and the white numbers represent the stored carbon. 

From the information presented, what would you predict to be the effect of a significant reduction in human contributions to the carbon cycle?

Analyze the quantitative model of carbon cycling presented in the diagram. Based on the values indicated by the yellow numbers (natural fluxes) and the red numbers (human contributions), statement is accurate about the carbon flux in the Earth's system?

The image shows annual emission data of CO2 from fossil fuel burning and the cement manufacturing industry as reported by British Petroleum. Based on the data, describes the trend of CO2 emissions from fossil fuel use and cement manufacturing over time?