PollutionIB MYP Biology: Subtopic test

1. 1
   A city in northern India has heavy traffic and a coal-fired power station. Residents report smoggy air, breathing problems and damage to the stonework of old buildings. The local coal contains sulfur, and many older engines burn their fuel in a limited supply of air.

   (a)

   Which pollutant is produced when fuel burns in a limited supply of air and is toxic because it reduces the oxygen carried by the blood?

   [1 mark]

   • ACarbon dioxide
   • BCarbon monoxide
   • CSulfur dioxide
   • DWater vapour

   (b)

   Which gas released by burning the coal is mainly responsible for acid rain?

   [1 mark]

   • ACarbon monoxide
   • BNitrogen
   • CSulfur dioxide
   • DHydrogen

   (c)

   Explain how burning the coal at the power station can cause acid rain.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A lake in a farming area in the UK has become green and cloudy each summer. Farmers spread fertiliser on the surrounding fields, and heavy rain washes some of it into the lake. A leaking sewage pipe also releases waste into one of the streams feeding the lake.

   (a)

   What is the name of the process that causes the lake to turn green and cloudy as a result of nutrients washed in from the fields?

   [1 mark]

   • ABioaccumulation
   • BGlobal warming
   • CDeforestation
   • DEutrophication

   (b)

   Why do many fish in the lake die after the algae die?

   [1 mark]

   • ABacteria decomposing the dead algae use up the oxygen in the water
   • BThe fish run out of nitrates to eat
   • CThe fertiliser makes the water too salty
   • DThe algae absorb all the heat from the water

   (c)

   Explain how the leaking sewage pipe could reduce the oxygen in the stream.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A pesticide that does not break down easily was sprayed on farmland next to a lake in Kenya. Scientists later measured its concentration in organisms from one food chain, in mg per kg of body tissue: 0.04 in microscopic plankton, 0.5 in small fish, 2.0 in large fish and 25 in fish-eating birds.

   (a)

   Describe the trend in the concentration of pesticide along the food chain, and calculate how many times greater the concentration is in the birds than in the plankton.

   [3 marks]

   (b)

   Explain how the pesticide reaches such a high concentration in the birds.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   Students at a school in Poland are worried about acid rain damaging the trees in a park near a coal-fired power station. At the same time, farmers near the school are being asked by the government to use less pesticide on their crops.

   (a)

   Outline an investigation the students could carry out in the laboratory to test the effect of acid rain on the germination of cress seeds.

   [6 marks]

   (b)

   Evaluate the use of pesticides by farmers.

   [6 marks]

   Total for question 4: 12 marks

End of questions