Practice Exam Questions
Explain the following terms that are used in ecology: Biosphere; Habitat; Consumer; Producer;
An organism that eats another organism is called a …
The place where an organism lives is called its …
What is a pyramid of numbers?
The primary source of energy in an ecosystem is the …
The parts of the earth and atmosphere in which life is found is called the …
In ecology what is meant by a trophic level?
Explain the following terms that are used in ecology: edaphic factor, symbiosis.
What is meant by nitrogen fixation?
10. What is meant by nitrification?
11. What is the function of the nitrogen cycle?
12. What term do ecologists use to describe an animal which kills and eats other animals?
13. Give four factors that influence the size of the human population.
14. If the population of prey declines suggest two possible consequences for the predators.
15. What is the principal source of energy for the Earth’s ecosystems?
16. Name a producer.
17. What is meant by an abiotic factor?
18. State one way in which a named organism is adapted to the ecosystem.
19. What is a quadrat frame?
20. Give two abiotic factors that you investigated, describe how you measured each one.
21. What term is used for the organism from which a parasite obtains its food?
22. What is a habitat?
23. List three abiotic factors that you investigated.
24. In the case of a named organism give an adaptation feature that you noted.
25. What is an ecosystem?
26. What does an ecologist mean by competition?
27. The use of one species to control the population of another species is called biological control.
Suggest one advantage and one disadvantage of biological control.
28. Name a group of organisms involved in nitrogen fixation.
29. What is meant by a pyramid of numbers?
30. A relationship between two organisms in which both benefit is called………..
31. In ecological studies it is found that the distribution of organisms is influenced by abiotic and
biotic factors. Distinguish between the underlined terms.
32. From an ecosystem that you have investigated give an example of an abiotic factor that
influences the distribution of a named plant in the ecosystem.
33. In the case of a named ecosystem give an example of a biotic factor that influences the
distribution of a named animal.
34. Construct a grazing food chain containing at least four trophic levels.
35. The conversion of atmospheric nitrogen to nitrates by bacteria is called …
36. Give two sources of the carbon dioxide that is found in the atmosphere.
37. Farmers add nitrates as fertilizers to the soil. They are advised not to spread fertilizers if heavy
rain is forecast. Why do you think they are given this warning?
38. Explain what is meant by pollution.
39. Give an example of pollution and describe how this form of pollution can be controlled.
40. Give an example of a human activity that results in the pollution of air or water
41. Explain what is meant by conservation.
42. Give a brief account of a conservation practice with which you are familiar.
43. Explain conservation in relation to wild plants and animals.
44. Suggest two reasons for conserving wild species.
45. State one conservation practice from agriculture or fisheries or forestry
46. Describe a human activity that may result in pollution. Suggest a way in which this pollution
could be prevented.
47. Suggest a possible effect on a human population that may result from an increased availability
of contraception.
48. Outline the problems associated with the disposal of waste. Suggest two ways of minimising
49. Waste management is becoming an increasingly difficult matter. Suggest two reasons for this.
50. Describe one method of waste management by reference to agriculture, fisheries or forestry.
51. Suggest some ways of minimizing waste.
52. Waste management is a matter of growing concern in Ireland as the population expands.
Outline three problems associated with waste disposal.
53. Give one example of the use of micro-organisms in waste management.
54. Suggest two ways to prevent or control pollution.
55. Write a short paragraph (about 5 lines) on waste management.
56. What term is used by ecologists to describe the organisms that form the base of a pyramid of
57. What is meant in ecology by a quantitative survey?
58. Give an example of an herbivore and of a carnivore found in an ecosystem you have studied
(not domesticated or farm animals).
59. What is meant by the term ‘fauna’?
60. In ecological studies what is a key?
61. Describe three methods used by plants to protect themselves from adverse external
62. Give an example of an edaphic factor.
63. Distinguish between quantitative and qualitative surveys in an ecosystem.
64. Why is a quadrat unsuitable for studying most animal populations?
65. Suggest a plant that would not be suitable to survey using a quadrat.
State one possible source of error in a survey of an ecosystem.
Decomposition is essential for the addition of nutrients to the soil. Explain the underlined term.
Name two groups of micro-organisms in the soil which are responsible for decomposition.
If all the primary producers were removed from an ecosystem (e.g. by disease) suggest
what would happen to the primary consumers?
Name an ecosystem you have studied and construct a simple food chain from that
Why are elements recycled in nature?
Is the following statement true or false? Give a reason for your answer. Food chains
are usually short.
Is the following statement true or false? Give a reason for your answer. The
herbivores in an ecosystem normally live long lives.
Is the following statement true or false? Give a reason for your answer.
The only remaining natural ecosystems in Ireland, for example mountain land above
the heather line and salt marsh, are ones for which mankind has no use.
Where are primary producers found in a pyramid of numbers?
Using named examples, construct a simple inverted pyramid of numbers.
Using a food web from your field study
Name one primary producer.
Name one herbivore and one carnivore from the web.
Name one omnivore from the web.
What would happen to the number of caterpillars if all the thrushes died in a habitat?
Name two pieces of apparatus used to collect animals from an ecosystem.
A situation in which one organism lives on or in a second species, feeding on it and causing it
harm is called _______________
Organisms capable of making their own food are called___________
A ________________ is all the members of a species living in an area
Micro-organisms and other organisms that return nutrients to the environment by decay are
called ______________
A situation in which two organisms of different species live together and at least one benefits
is called ________________
__________________ is a struggle between organisms for a scarce resource.
One organism killing and eating another organism is called _______________
Distinguish between contest competition and scramble competition by writing a sentence about
Name a factor, other than competition, that controls wild populations.
What deduction is it possible to make from each of the following observations?
(i) In a particular area the population of a predator did not decline following a big reduction
in the population of its main prey.
(ii) Mortality levels resulting from infection by a particular virus tend to decline over the years.
(iii) Where some members of a species remain in the same general area throughout life and
some members are migratory, mortality levels tend to be higher in the migratory part of the
(iv) There is a greater variety of herbaceous (non woody) plants in areas where grazing
species, such as rabbits, are more plentiful than in areas where grazing species are less
(v) In some species of migratory ducks in the northern hemisphere it is found that the
wintering grounds of the males lie further south than those of the females.
Organisms that are introduced into new environments outside their natural ranges are referred
to as exotic species. In some cases these introductions have been deliberate and in other cases
accidental e.g. when a species kept in captivity in a new country escapes and gives rise to a
wild population. Worldwide, the great majority of deliberate attempted introductions have been
(i) Suggest a reason for attempting to establish an exotic species in a new country.
(ii) Suggest two reasons why the great majority of attempted introductions have been
(iii) Use your knowledge of the life cycle of flowering plants to suggest how an exotic plant
may escape from captivity.
(iv) Use the knowledge that you have gained in your studies of ecology to suggest how the
introduction of an exotic species may:
1. impact negatively on an existing community.
2. impact positively on an existing community.
91. It has been stated that an exotic species has a good chance of becoming established in a new
environment if there is a vacant niche.
1. Explain the term niche in this context.
2. Do you agree with the above statement?
3. Explain your answer.
Explain the terms 1. Flora, 2. Fauna.
Name one animal from a named ecosystem and describe how you carried out a quantitative
study of that animal.
Suggest one way in which marking an animal might endanger it.
Ecosystems are subject to changes, both natural and artificial. Mention one of each type of
change as it applies to your named ecosystem.
Match one of the terms from the list with each description. List: Pollution; Niche; Recycle;
Burning fuel; Conservation; Smell.
(a) Any harmful addition to the ecosystem.
(b) A problem associated with waste disposal.
(c) A way to minimise waste.
(d) Wise management of an ecosystem.
(e) A possible cause of pollution.
(f) The role of the organism in the habitat.
Using organisms from the ecosystem you have studied, draw a pyramid of numbers to show at
least three feeding levels.