The crustacean and the jellyfish obtain carbon compounds by feeding. State one source of carbon for marine organisms, other than feeding.

In the diagram, which of the processes labelled A to D transfers the largest mass of carbon per year in a woodland ecosystem?

[Source: © International Baccalaureate Organization 2019]

Referring to the data, compare and contrast the changes in the use of the different fuels between 1950 and 1975.

Outline the trends shown in the data in the graph.

The structure of organisms is based on organic molecules containing carbon. Explain the cycling of carbon in an ecosystem.

The table shows the global carbon budget over two decades; the years 1990 to 1999 and 2000 to 2009.

[Source: © International Baccalaureate Organization 2019]

Using the table, explain causes of the changes in carbon flux over the two decades.

Suggest reasons for the differences in the numbers of oysters drilled, as shown in the bar charts.

The diagram shows the carbon flux in gigatonnes per year between some of the Earth’s global reservoirs.

[Source: Figure 7.3 and Table 7.1 from Denman, K.L., G. Brasseur, A. Chidthaisong, P. Ciais, P.M. Cox, R.E. Dickinson, D.
Hauglustaine, C. Heinze, E. Holland, D. Jacob, U. Lohmann, S Ramachandran, P.L. da Silva Dias, S.C. Wofsy and
X. Zhang, 2007: Couplings Between Changes in the Climate System and Biogeochemistry. In: Climate Change
2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the
Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt,
M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.]

What can be deduced from the information in the diagram?

A. Arrows S are mainly due to respiration of marine plants and animals.

B. Photosynthesis is a component of both arrows Q and S.

C. Every day, more carbon is removed from the ocean than is added.

D. Ocean carbon is stored as dissolved calcium carbonate.

The radula in a gastropod is hard but not made of calcium carbonate. Outline how this statement is supported by the drilling success of the gastropods in seawater with normal or high CO₂ concentrations.

Calculate the percentage increase in the use of liquid fuels from 1950 to 1975.

%

Outline the role of methanogenic archaeans in the movement of carbon in ecosystems.

Describe how autotrophs absorb light energy

State one process that results in the loss of carbon dioxide from a marine organism such as a crustacean or a jellyfish.

Describe the process of peat formation.

Explain the transformations of carbon compounds in the carbon cycle.

The diagram shows the carbon cycle.

[Source: © International Baccalaureate Organization 2017]

Which two processes correspond to the labelled arrows?

A. K is combustion and L is catabolism.

B. J is anabolism and K is respiration.

C. J is combustion and K is respiration.

D. J is anabolism and L is catabolism.