MCQ-2: Human Influences on Ecosystems

The diagram shows a population pyramid for a city.

What feature of the population is shown in the diagram?

What are the possible effects of deforestation?

A farmer put some fertiliser on his field. Soon afterwards, there was a heavy storm and some of the fertiliser drained into a lake.

What is the effect of the fertiliser on the growth of the crop plants in the field and the plants in the lake?

In 2005, fifteen mice were set free on an island where mice had never lived before. The table shows how their population changed over the next three years.

What caused the population change shown in the table?

What is reduced when untreated sewage is released into rivers?

The diagram shows a food chain.
A farmer sprays his cabbages with pesticide.
Which organisms does the farmer want to kill?

Which pollutants of water can lead to eutrophication?

What is an effect of pollution by nuclear fall-out?

The table shows the birth rates and death rates in four countries.
Which country will double its population most quickly?

Which two gases both contribute to global warming?

Lichens are organisms that do not grow well in air containing sulfur dioxide.
Which graph shows the change in number of lichen species from the centre of an industrial city to the countryside 15 km away?

The graph shows how the population of the world has increased from 1650 until the present day.

What stage in the sigmoid population growth curve is represented by region P?

Which effect is least likely to occur as a result of deforestation?

The diagram shows the positions of four farms and the concentrations of nitrate at different points in a river.
Which farm is likely to have been using too much fertiliser on its land?

A large amount of herbicide is applied to a field. However, some of the herbicide is washed into a nearby lake.
What is the effect of the herbicide on the weeds in the field and on the plants in the lake?

The graph shows the levels of dissolved oxygen and mineral ions in a river.
At which point does raw sewage enter the river?

Deforestation can have a negative impact on the environment.
Which statement about the negative impact of deforestation is correct?

When nitrates enter a lake they cause rapid growth of algae on the surface of the water. This causes the following changes in the lake:

1. a decrease in the concentration of dissolved oxygen in the water
2. fish and other aquatic animals die
3. an increase in aerobic respiration by decomposers
4. producers die and decomposition increases

In which order do these changes occur?

What would be unlikely to increase the risk of human famine?

Since 1970 sulfur dioxide emissions have dropped by 95% in some parts of the world.
What is the main reason for the reduction in emissions?