Air pollution

6 (a) Using the recommended amount of fertiliser on a crop increases crop yield. Some farmers think that adding extra fertiliser will give an even greater crop yield.

Give a reason why adding extra fertiliser does not result in an even greater crop yield.

Some farmers apply more nitrogen fertiliser and more water to their fields than are needed. Explain the biological consequences of applying more nitrogen fertiliser and more water than needed.

The atmosphere can be polluted by gases such as carbon monoxide released from industry. Describe the effects of carbon monoxide on the human body.

Which of these is not a greenhouse gas?

Megalodon was an animal.

Which of these features does megalodon share with the fungus yeast?

1 nuclei present in cells

2 nervous coordination

3 stores carbohydrate as glycogen

Scientists think that the giant, predatory toothed whales that replaced the extinct megalodon consumed the same sources of food.

Explain how the evolution of giant, predatory toothed whales may have caused the extinction of megalodon. (lines 5 to 7)

Volcanoes release sulfur dioxide into the atmosphere.

Describe the biological consequences of sulfur dioxide release. (lines 10 to 12)

The release of large amounts of dust into the atmosphere reduced light intensity.

Explain why this would cause a loss of food chains. (lines 9 to 11)

Explain why the cells in cryozoos are put in salt and sugar solution rather than pure water. (lines 16 to 18)

Describe how scientists could clone a banteng. (lines 18 to 20)

Explain why releasing cloned mammoths could have negative and positive effects on Arctic biodiversity. (lines 22 to 28)

Large quantities of food are wasted every year. Waste food needs to be disposed of using methods that do not harm the environment.

The table shows the mass of each gas released into the air from three different methods of waste disposal.

Calculate how much carbon dioxide would be released from 125 kg of waste food when using an anaerobic digester.

Give your answer to two significant figures.

Some scientists have claimed that anaerobic digesters are the most environmentally friendly method of waste disposal.

Evaluate this claim using data from the table and your own knowledge.

Pollution of air or water can affect ecosystems.

Explain the biological consequences of air pollution by sulfur dioxide.

State how sulfur dioxide pollution can be reduced.

Some scientists have suggested that adding hydrogencarbonate solution to soil, instead of adding water, can increase plant growth.

Design an investigation to discover the effect that adding hydrogencarbonate solution has on the growth of seedlings.

Include experimental details in your answer and write in full sentences.

Lichens are organisms that grow well on stone walls in unpolluted air. Lichens grow less well in polluted air. Car exhaust fumes contain sulfur dioxide that pollutes air. A scientist investigates the effect of pollution by cars in a city. This is her method.

• measure the percentage area of a stone wall in the city centre covered by lichen

• repeat this measurement at different distances from the city centre

The table shows her results.

Explain the results shown in the table.

Describe a method to measure the percentage of a stone wall covered by lichen.

Adding water to a powder called sodium metabisulphite will release sulfur dioxide gas. Devise a laboratory investigation to find out the effect of sulfur dioxide gas on the heat released by germinating seeds. Include experimental details in your answer and write in full sentences.

Pollution can occur in the atmosphere and in rivers.

Carbon monoxide can pollute the atmosphere. Describe the effects of carbon monoxide pollution on humans.

Water pollution can occur if sewage enters a river. Explain the biological consequences of sewage pollution on a river ecosystem.