Practice IB Biology Topic D4.3 Climate Change with authentic exam-style questions for both SL and HL students. This question bank focuses on the exact syllabus content for D4.3 Climate Change and mirrors Paper 1A, 1B, 2 style where relevant.
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Coral colonies were grown for eight weeks under identical light. Which conclusions are independently supported?
Understanding biological processes helps address global environmental challenges.
Restoring peat-forming wetlands is promoted as a way to sequester carbon.
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(e) Using Table 1 and Figure 1, why peak caterpillar biomass advanced more than great-tit hatching.
(f) Figure 2 shows the mean number of chicks fledged per pair against the mismatch, defined as the number of days by which hatching follows the caterpillar peak. Points show means ±1 standard deviation.
Figure 2: Mean number of chicks fledged per pair against the mismatch in days (points ±1 SD).
Using Figures 1 and 2, the effect of the changed timing on great-tit breeding success.
(g) how this mismatch could drive the evolution of earlier breeding in the great-tit population.
(h) why the great-tit population might still decline despite this natural selection.
| Seawater pH | Temperature / °C | Relative calcification / % | Bleached colonies / % |
|---|
| 8.1 | 26 | 100 | 6 |
| 7.7 | 26 | 61 | 7 |
| 8.1 | 31 | 96 | 72 |
(a) the process of photophosphorylation in the light-dependent reactions of photosynthesis.
(b) how increased carbon dioxide concentration may affect protein synthesis in marine organisms.
(c) how climate change can disrupt photosynthesis and food webs.
In oak woodlands, great tits (Parus major) time their breeding so that peak demand from their chicks coincides with the peak biomass of the caterpillars they feed them.
Figure 1 shows the day of the year of peak caterpillar biomass and of the mean great-tit hatching date from 1980 to 2020.
(a) Using Figure 1, the day of the year of peak caterpillar biomass in 1980.
(b) Using Figure 1, the number of days by which the caterpillar peak advanced between 1980 and 2020.
(c) Using Figure 1, that the timing of the two events has diverged over the period.
(d) Table 1 gives the mean April temperature in the woodland by decade.
| Decade | Mean April temperature / °C |
|---|---|
| 1980s | 8.0 |
| 1990s | 8.6 |
| 2000s | 9.2 |
| 2010s | 9.8 |
Using Table 1, the increase in mean April temperature from the 1980s to the 2010s.
Which statement describes the mechanism by which increased atmospheric carbon dioxide contributes to the enhanced greenhouse effect?
Lower pH increases calcification; higher temperature reduces bleaching
Lower pH increases calcification; higher temperature increases bleaching
Lower pH suppresses calcification; higher temperature increases bleaching
Lower pH suppresses calcification; higher temperature reduces bleaching
