DP Biology Questionbank

(i) Describe the trend in calcification when the pH is decreased at 25 –26°C.

(ii) In environmental studies, a critical value is the level at which a population declines or shows signs of poor health. Suggest a critical pH for P. onkodes.

(iii) Using all of the data, comment on the hypothesis that ocean acidification in warming seas will have the same effect on all species of coral.

Calculate the difference in coral cover in 1996 and 2002. No working required.

Outline causes of ocean acidification.

Describe the evidence that the ocean temperature has an effect on coral cover.

Comment on whether the experimental data supports the observed data from the ocean.

Outline reasons for the change occurring at Z. 

The short-tailed albatross (Phoebastria albatrus) nests and breeds on remote low-lying coral islands in the Pacific Ocean. Predict how global warming may threaten the survival of such an ocean bird.

The graph shows atmospheric oxygen levels over time.

About 2.5 billion years ago, a significant rise in atmospheric oxygen occurred. What was the cause of this rise?

A. Photosynthesis by non-vascular land plants

B. Photosynthesis by vascular land plants

C. Oxygen produced by photosynthetic bacteria being released from the ocean into the atmosphere

D. Volcanic activity

Which gases have made the most significant contributions to global warming?

A. Water and carbon dioxide

B. Carbon dioxide and methane

C. Methane and nitrous oxide

D. Carbon dioxide and ozone

Discuss the relationship between atmospheric carbon dioxide concentration and global temperatures.

The map shows the widespread distribution of coral reef ecosystems (indicated by black dots) in the world’s oceans. Death of coral reefs is related to increasing atmospheric carbon dioxide concentrations.

[Source: National Oceanic and Atmospheric Administration, 2021. Where Reef Building Corals Found. [map online] Available at: https://oceanservice.noaa.gov/education/tutorial_corals/media/supp_coral05a.html [Accessed 20 May 2021].]

Explain how increased atmospheric carbon dioxide concentrations can lead to coral death.

Suggest a reason for a larger percentage of corals being infected with white syndrome on reefs with a higher cover of corals.

Compare and contrast the data for 1998–1999 and 2002–2003.

Describe the evidence that is provided by the data in the table for the harmful effects of rising sea temperatures on corals.

The researchers concluded that there was a threshold coral cover percentage, below which infection rates tended to remain fairly low. Using the data in the table, identify this threshold level.

Some scientists predict that, if humans continue to produce carbon dioxide at the current rate, the pH of the oceans will become more acidic. Suggest possible effects on the coral reefs.

Explain how increased carbon dioxide in the air leads to the greenhouse effect.

Calculate the increase in mean global temperature between 1880 and 2010.

.......... °C

Outline how greenhouse gases interact with radiation and contribute to global warming.

Deforestation and agricultural activities including the production of crops and livestock are thought to play a major role in the greenhouse effect. The graph shows annual trends in rates of deforestation and the production of soybeans and cattle in the state of Mato Grosso in Brazil in the period from 2001 to 2010.

[Source: 'Decoupling of deforestation and soy production in the southern Amazon during the late 2000s.'
Marcia N. Macedo, Ruth S. DeFries, Douglas C. Morton, Claudia M. Stickler, Gillian L. Galford, and Yosio E.
Shimabukuro PNAS January 24, 2012, 109 (4) 1341–1346; https://doi.org/10.1073/pnas.1111374109,
used with permission]

What conclusion can be drawn from the information in this graph?

A. The decline in rates of deforestation led to an increase in production of CO2.

B. Soybean production accounted for a greater proportion of deforestation than cattle production.

C. Forest habitats declined during the first few years of the study.

D. The decline in rates of deforestation is due to an increase in soybean production.