Ecology & Evolution End of Topic Test
1.
What term refers to a community and its abiotic environment?
A.
Biosphere
B.
Ecosystem
C.
Habitat
D.
Niche
(Total 1 mark)
2.
Which organisms externally digest dead organic matter and then absorb the nutrients?
A.
Autotrophs
B.
Detritivores
C.
Heterotrophs
D.
Saprotrophs
(Total 1 mark)
3.
The diagram below is a simplified version of a food web from Chesapeake Bay. The arrows indicate the
direction of energy flow and the numbers indicate species within the food web.
At which trophic level or levels does species II function?
A.
2nd and 3rd consumer
B.
3rd consumer
C.
3rd and 4th consumer
D.
Producer
(Total 1 mark)
1
4.
What name is given to an organism that is able to manufacture its own food from simple chemical
materials?
A.
Heterotroph
B.
Saprotroph
C.
Autotroph
D.
Detritivore
(Total 1 mark)
5.
What is an advantage of estimating plant populations by random sampling using quadrats?
A.
Accurate estimates can be obtained more quickly than if every plant in the population is counted.
B.
Random samples can be taken from the most convenient parts of the habitat.
C.
Numbers of plants in each quadrat can be estimated quickly.
D.
Marking and recapture of plants is not necessary.
(Total 1 mark)
6.
In the graph below, what could be causing the population change in the region II  III?
A.
Natality > mortality, immigration = emigration
B.
Natality > mortality, immigration > emigration
C.
Natality > mortality, immigration < emigration
D.
Natality = mortality, immigration < emigration
(Total 1 mark)
7.
What is a factor that increases the greenhouse effect and what is a consequence of it?
Factor contributing to increases
in the greenhouse effect
A.
Increasing global temperatures
B.
Rising sea levels
C.
Increasing global temperatures
D.
Increases in air travel
Consequence of the increased
greenhouse effect
Rising sea levels
Increasing global temperatures
Burning fossil fuels to run air conditioning
Increasing global temperatures
(Total 1 mark)
8.
What are the main sources of carbon dioxide on earth?
A.
Cellular respiration of consumers, producers and combustion of fossil fuels
B.
Photosynthesis and cellular respiration of consumers
C.
Cellular respiration of producers and combustion of fossil fuels
D.
Photosynthesis and combustion of fossil fuels
(Total 1 mark)
9.
According to the precautionary principle, what should happen if there are fears that eating a food might
cause a health problem?
A.
People should be warned about the possible health problem.
B.
The company producing the food should be warned about the possible health problem.
C.
People who have fears about the food should test it to see if it causes a real health problem.
D.
The company producing the food should test the food to prove that it does not cause a health
problem.
(Total 1 mark)
10.
What is natural selection?
A.
The mechanism that increases the chance of certain individuals reproducing.
B.
The mechanism that leads to increasing variation within a population.
C.
The cumulative change in the heritable characteristics of a population.
D.
The mechanism that explains why populations produce more offspring than the environment can
support.
(Total 1 mark)
3
Use lined paper to answer questions 11 to 16.
11.
In communities, groups of populations live together and interact with each other. Outline the importance
of plants to populations of other organisms in a community.
(Total 6 marks)
12.
Outline ways in which leaves take part in the carbon cycle in ecosystems, apart from photosynthesis.
(Total 4 marks)
13.
Ecologists sometimes investigate one population and at other times do research into a whole community.
Define the terms population and community.
(Total 4 marks)
14.
Describe with the aid of a diagram the phases of a sigmoid population growth curve.
(Total 4 marks)
15.
Outline the quadrat method of random sampling used to determine the population of a plant species.
(Total 6 marks)
16.
Explain evolution of a species by natural selection in response to environmental change.
(Total 7 marks)
17.
The relationship between the numbers of rodent species and rainfall was studied in dry areas of Chile and
in the south-west of the United States. The results of the study are shown in the scattergraph below.
K
ey:
Chile
U
SA
8
6
N
um
berofspecies
4
2
0
10
50
100
500
Rainfall / m
m
[Source: UNEP, (1995), Global Biodiversity Assessment, Press Syndicate of the University of Cambridge, page 154]
(a)
Calculate the difference between the number of species found at 80 mm of rainfall and at 100 mm
of rainfall in
(i)
Chile.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
the USA.
...........................................................................................................................
...........................................................................................................................
(1)
(b)
Compare the relationship between the number of rodent species and rainfall in Chile with that of
the USA.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
5
(c)
Suggest two reasons for the relationship between the number of rodent species and rainfall in each
country.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 6 marks)
18.
(a)
State the unit that would be used for each bar in a pyramid of energy.
.....................................................................................................................................
(1)
(b)
Distinguish between predation and parasitism.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(c)
Discuss the difficulties when classifying organisms into trophic levels.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(3)
(Total 6 marks)
Copepods are very small crustaceans and an important component of plankton in the Arctic sea ice. The
distribution of copepods, which feed on microalgae, can be related to the food and predators. The
biomass of microalgae was measured and the concentration of chlorophyll a was calculated. The graphs
below show how the concentration of chlorophyll a and copepods change with depth.
Microalgae
Copepods
Chlorophyll a/ mgm–3
Relativenumbers
Depth / m
Depth / m
19.
[Source: Martin Fortier, et. al., Visual predators and the diel vertical migration of copepods under Arctic sea ice during the midnight sun”
(2001), vol. 23, issue 11, pp. 1263–1278, by permission of Oxford University Press]
(a)
State the amount at a depth of 30 m below sea level of
(i)
chlorophyll a;
..........................................................................................................................
(ii)
copepods.
..........................................................................................................................
(2)
(b)
Describe the distribution of microalgae.
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
(2)
7
(c)
Discuss factors that could affect the distribution of copepods.
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
(3)
(Total 7 marks)
20.
Phenologists are biologists who study the timing of seasonal activities in animals and plants, such as the
opening of tree leaves and the laying of eggs by birds. Data such as these can provide evidence of climate
changes, including global warming.
The date in the spring when new leaves open on horse chestnut trees (Aesculus hippocastaneum) has been
recorded in Germany every year since 1951. The graph below shows the difference between each year’s
date of leaf opening and the mean date of leaf opening between 1970 and 2000. Negative values indicate
that the date of leaf opening was earlier than the mean. The graph also shows the difference between each
year’s mean temperature during March and April and the overall mean temperature for these two months.
The data for temperature was obtained from the records of thirty-five German climate stations.
4
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4
1
9
7
0
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9
8
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Y
e
a
r
[Source: Walther et al., Nature (2002), 416, pages 389–395]
(a)
Identify the year in which there was the
(i)
earliest opening of horse chestnut leaves;
...........................................................................................................................
(1)
(ii)
lowest mean temperature in March and April.
...........................................................................................................................
(1)
(b)
Use the data in the graph to deduce the following.
(i)
The relationship between temperatures in March and April and the date of opening of leaves
on horse chestnut trees.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Whether there is evidence of global warming towards the end of the twentieth century.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
9
From 1973 onwards phenologists in the Netherlands have been studying a population of great tits (Parus
major) in a forest on the Hoge Veluwe. Nest boxes are checked every week to find out when the great tits
lay their eggs and how many eggs they lay. Young birds are ringed when they are seven days old, to
allow the reproductive success of their parents to be monitored. Great tits feed on arthropods, especially
caterpillars. The phenologists found that the date of maximum caterpillar biomass each year in the forest
could be estimated accurately using temperature records. The graphs below show the mean date of egg
laying and the estimated date of maximum caterpillar biomass for each year from 1973 to 1995.
45
35
Mean date of egg
laying / number of days
after 31 March
25
15
5
75
65
Mean estimated date of
maximum caterpillar
biomass / number of
days after 31 March
55
45
35
1972
1976 1980 1984 1988 1992 1996
Year
[Source: Visser, Noordwijk, Tinbergen and Lessells, Proceedings of the Royal Society of London,
(1998), 265, pages 1867–1870]
(c)
(i)
Compare the date of egg laying with the date of maximum caterpillar biomass.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Suggest an advantage to great tits of the difference in dates.
...........................................................................................................................
...........................................................................................................................
(1)
(d)
State the trend, shown in the graph, for the date of maximum caterpillar biomass.
.....................................................................................................................................
.....................................................................................................................................
(1)
There was no statistically significant change in the date of egg laying between 1973 and 1995, but the
phenologists found evidence that natural selection will eventually cause a change in the date of egg
laying.
(e)
Explain how natural selection could cause a change in the date of egg laying in the population of
great tits in the forest on the Hoge Veluwe.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 10 marks)
11