Ecosystems (Cambridge (CIE) IGCSE Environmental Management): Exam Questions

Exam code: 0680

14 mins7 questions
1
2 marks

Figure 6.1 shows water hyacinth plants in a river ecosystem.

Water hyacinth on a river
Figure 6.1 Adoscam, CC BY-SA 4.0, via Wikimedia Commons

Water hyacinth plants reduce the growth of other aquatic plants by competition.

Suggest two ways water hyacinth plants compete with other aquatic plants.

2
1 mark

Figure 6.1 shows water hyacinth plants in a river ecosystem.

Water hyacinth on a river
Figure 6.1 Adoscam, CC BY-SA 4.0, via Wikimedia Commons

Water hyacinth plants are not native to this river ecosystem.

State the term for an organism living in an ecosystem they are not native to.

3
2 marks

Water hyacinth plants produce flowers above the surface of the water. These flowers are pollinated by two different methods.

Suggest two ways that water hyacinth flowers are pollinated.

4
2 marks

Complete the sentences about the events that occur in a flower after pollination.

After pollination, the flower is ..........

This allows the formation of fruits and ..........

5
3 marks

Figure 6.2 shows a food web containing water hyacinth plants.

Food web diagram; arrows point from food to feeder. Water hyacinth plant is eaten by weevil, raccoon and snail; weevil by raccoon; snail by egret; and raccoon and egret by eagle.
Figure 6.2

Use Figure 6.2 to identify:

all the primary consumers

the organism that only feeds as a secondary consumer

the organism that feeds at trophic levels two and three

6
2 marks

The snails contain 100 units of energy.

Food-chain diagram showing water hyacinth plant → snail → egret → eagle. The snail box states “100 units”; dotted lines beneath the plant, egret and eagle labels are for entering energy values.
Figure 6.3

Complete Figure 6.3 to show the units of energy in the food chain.

7
2 marks

Giant African land snails are an invasive species in Florida.

Suggest two other reasons why scientists are concerned about the populations of giant African land snails in Florida.