UNIVERSITY OF MALTA
THE MATRICULATION CERTIFICATE EXAMINATION
INTERMEDIATE LEVEL
ENVIRONMENTAL SCIENCE
May 2007
EXAMINERS’ REPORT
MATRICULATION AND SECONDARY EDUCATION CERTIFICATE
EXAMINATIONS BOARD
IM EXAMINERS’ REPORT MAY 2007
IM Environmental Science
May 2007 Session
Examiners’ Report
Part 1: Statistical Information
A total of 565 candidates applied for the examination. Table 1 shows the distribution of
grades for this session as compared with the results of the previous year:
Table 1: Distribution of Grades awarded in May 2007 compared to May 2006.
Grade
A
B
C
D
E
F
Abs
Total
Number
30
50
155
102
112
96
20
565
% of Total 2007
5.3
8.9
27.4
18.1
19.8
17
3.5
100%
% of Total 2006
6.0
11.9
38.6
14.5
18.5
7.9
2.7
100%
Part 2: Comments on candidates’ performance
Section A
Q1. Most answers given were correct except when candidates used the term earthquakes
instead of the correct term weathering – this is probably due to the words ‘splits’ and
‘breaks down’ in the same sentence. Candidates normally associate such descriptions
with earthquakes. There was also some confusion when it came to differentiating the
rock formation types in this case igneous being mistaken for sedimentary or vice versa.
Q2. For part (a) dealing with the earth structure, the terms given were overall correct in the
majority of cases showing that candidates are familiar with the different layers that
constitute the earth. The main problems were seen in part (b) where the candidates
were expected to give a characteristic of each constituent layer. Many candidates failed
to distinguish between outer and inner core composition giving incorrect answers to
both chemical compositions as well as the actual state of each layer. Few candidates
mentioned that the crust is made up of both oceanic and continental plates. Most of the
answers given for this part lacked the required scientific descriptions.
Q3. Marks scored in this question ranged from average to low scores – it seems that the
candidates had problems visualising the flow diagram normally associated or given for
the water cycle. In fact there were a number of incorrect answers for the three parts of
the question – typical answers for part (i) included clouds; for part (ii) wells and
reservoirs were amongst the common answers given; and for part (iii) most candidates
gave evaporation and condensation for answers.
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IM EXAMINERS’ REPORT MAY 2007
Q4. Candidates had very low scores for this question for both parts (a) and (b). In part (a)
very few candidates mentioned the unequal heating of the earth due to latitudes and
stated simply that the main cause of atmospheric circulation is due to high and low
pressures. This same answer was repeated for part (b) while attempting to describe a
Hadley cell. A small number of candidates went into more detail stating that warm air
rises at the equator to be cooled once again at the poles, however, there was no link to
different air densities and very often this same description was confused with what
happens in the water cycle when condensation occurs in the sky and rain falls as a
result. Such answers seem to corroborate the suspicion that candidates tend learn
details by heart and just reproduce facts without really understanding what the question
requires.
Q5. For part (a) the definition of the term tide simply referred to the rising of sea water and
there was ample confusion as it was often associated with tsunamis and tidal waves
phenomena. For part (b) the majority of candidates were aware that tides are caused by
the gravitational pull of the moon. A few mentioned the gravitational pull of the sun as
well and still a smaller number incorrectly stated that tides are the result of the Earth’s
magnetic field.
Q6. Most candidates scored high marks in this question, the principal mistakes being the
misunderstanding of the terms Biomagnification and Bioaccumulation. A number of
candidates also attributed the device to remove solid particles from smoke being emitted
to a catalytic converter rather than the electrostatic precipitator.
Q7. A spectrum of answers was given for this question. There were candidates who showed
that they were prepared and gave clear concise correct answers to all parts. Others tried
to produce some form of definition for the terms primary and secondary pollutants,
failing miserably in the process, but giving correct examples of both. Then there was the
final group who failed to give any correct answers.
Q8. This question was one where several candidates fared miserably; the worst answers
were those for the sources of VOC and Ozone contrasting sharply with correct answers
given for sources for Oxides of sulphur and nitrogen. Similar answers were given for
the effects of the respective pollutants.
Q9. In the first part of the question most candidates could describe the graph, but few could
interpret what happened to the two populations and so lost a number of marks. In part
(b) a number of candidates confused carrying capacity with biodiversity and stated that
it is the number of different species supported by the environment. Only a very small
number of candidates knew how to work out the doubling time of a population in part
(d). Nearly all candidates gave an accurate answer to part (e).
Q10. This question was quite straightforward and did not pose any serious difficulties for the
majority of the candidates. Most candidates could distinguish between the two terms
except for part (c) where a substantial number gave answers that showed that they had
no idea what a fundamental and a realized niche were.
Q11. A good number of candidates could express the concept of a biome in part (a) although
not giving a full answer. Surprisingly enough a considerable number of candidates
could list three major terrestrial biomes but did not know which biome is most
commonly found in Malta.
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IM EXAMINERS’ REPORT MAY 2007
Section B
Q1. This was the second most attempted question from this section. For part (a) it was very
common for candidates to reuse the language and the description given in the
introductory quote of this same question showing that candidates were not very familiar
with what sustainable development entails. Other typical answers included the use of
alternative sources of energy, the waste disposal system and the recycling of materials
namely plastic and paper.
In part (b) a small number of candidates stated that renewable sources of energy were
those that never finish, however they went on to give examples that included paper and
plastic as they confused the recycling of waste material with the alternative use of
energy sources. However, the majority of candidates were familiar with solar energy
and water and tidal energy and gave correct answers both for the renewable sources of
energy as well as for the non renewable sources of energy. In fact most candidates
scored full marks in this part.
The main difficulties were experienced in part (c) where answers where more often than
not completely out of point. The candidates seemed to give back what they have learnt
as part of their lectures irrespective of what was actually being asked and so most
answers referred to the greenhouse effect, the use of CFC’s and the recycling of waste
material. Only one or two candidates referred to the actual extraction of abiotic sources
and the subsequent effects this was having on the environment. This once again
evidenced the predominant method of study. i.e. learning a number of standard answers
and then fitting them to the question irrespective of what was asked.
Q2. This was the most attempted question from this section. For part (a) candidates scored
high marks in the three parts of this question giving correct descriptions and
explanations of the effects that agriculture is having on the local environment. However
part (iii), referring to the reduction of habitats and biodiversity was the least discussed very few candidates wrote about land clearing not as a direct result of agricultural
practice but rather due to building construction. Sometimes candidates forgot that the
question was dealing with agriculture and even in part (ii) when writing about pollution
they gave examples of air (e.g. increase in traffic) and water pollution (e.g. disposal of
sewage in the water channels) rather than situations arising from agricultural practices.
These answers were considered out of point.
In part (b), the majority of candidates scored very high marks since they were aware of
different and alternative soil conservation techniques. Typical answers included crop
rotation, contour farming and building of rubble walls together with terracing. In part
(c) the marks scored were slightly lower since it seems that they failed to understand
what was actually being asked. In fact on several occasions, candidates just repeated
what they had stated in part (b). Typically candidates associated sustainable agricultural
practices only with the reduction of the use of pesticides.
Q3. Although a popular question with candidates, this proved rather difficult to answer,
most candidates producing vague answers and scoring low marks. A good number of
candidates shot off course by giving detailed essays about waste and waste management
and related problems in Malta. This seems to indicate that candidates hoped to score
marks simply by giving long elaborate and fruitless answers in the form of long essays
irrespective of their relevance to the question. Conversely, it might indicate that
candidates were unable to understand what the question required but looked for key
words and started writing something about the theme.
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IM EXAMINERS’ REPORT MAY 2007
Q4. This question was another popular question where candidates scored relatively high
marks. This showed that the candidates were very well prepared about global warming
and greenhouse gases, these being contemporary themes being discussed everyday in
the media. The main problems encountered by candidates related to the origin of the
Greenhouse effect, some even attributing the term to the Kyoto Protocol rather than to
the agricultural greenhouse. A number of candidates lost marks on the schematic
diagram due to the fact that they failed to include certain details such as the fact that the
incoming waves have a short wavelength and the reflected ones are of a longer one. A
few gave a sketchy diagram lacking the required details.
Q5. In part (a) nearly all candidates who chose this question seemed to have the impression
that keystone species and producers are one and the same thing. The reasons given
were that producers are found at the base of each food chain and thus without them food
webs would collapse. Very good answers were given by candidates in part (b) which
shows that succession was a familiar topic with candidates. The majority of candidates
could define the concept of a climax community but none could give two correct
reasons as to why it exhibits a higher level of stability than that found in other stages.
Q6. In part (a) which dealt with specific examples of overcoming the problem of overfishing
many candidates gave logical solutions to how to go about it – typical answers included
the use of fish farms, legislation, reducing mesh size, and educational programmes. A
substantial number of candidates failed to get any marks in part (b) since they did not
know what the term logging means and gave answers which had nothing to do with the
question. Many candidates gave valid problems associated with grazing in part (c).
General Comments
The examiners point out common problems that have been resurfacing in every
examination session:
(a) a general inability to express themselves in correct English. Spelling mistakes,
particularly of technical terms, was also quite common;
(b) low level of understanding of scientific concepts. At times even basic scientific
knowledge was lacking in the answers provided;
(c) the presentation of ‘model essays’ irrespective of what the question requested.
Chairperson
Board of Examiners
July 2007
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