PollutionIB MYP Biology: Mind map

Exam questions on Pollution

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.
   Explain how burning the coal at the power station can cause acid rain.2 marks
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.
   Explain how the leaking sewage pipe could reduce the oxygen in the stream.2 marks
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.
   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