Climate Change (DP IB Biology: SL): Exam Questions

The image below shows two shells from marine organisms. Both shells were placed in a saltwater solution for 45 days; shell A at pH 8.5 and shell B at a pH of 7.

Explain the results shown in the image.

Outline the relevance of increasing atmospheric carbon dioxide levels to the results shown in part (a).

Describe a process that removes carbon dioxide from the atmosphere other than that referred to in part (b).

Outline the impacts of increasing average global temperatures.

Outline some of the impacts of increasing average global temperatures.

Describe conservation approaches that aid carbon sequestration.

Methane is an example of a greenhouse gas that commonly occurs in the atmosphere. The graph below shows the main sources of methane as well as the percentage contribution of the different components of each source. A teragram (Tg) equals 10¹² grams and is equivalent to one megatonne (1 million tonnes).

Calculate the amount of methane, in Tg year^-1, that is released from wetlands. Show your working.

One mark is available for clarity of communication throughout this question.

Suggest the possible impact that an increase in global temperatures would have on the polar regions, as well as the global consequences of this impact.