UNIVERSITY OF MALTA
THE MATRICULATION CERTIFICATE EXAMINATION
ADVANCED LEVEL
BIOLOGY
May 2006
EXAMINERS’ REPORT
MATRICULATION AND SECONDARY EDUCATION CERTIFICATE
EXAMINATIONS BOARD
AM EXAMINERS’ REPORT MAY 2006
AM Biology
May 2006 Session
Examiners’ Report
Part 1: Statistical Information
Table 1 shows the distribution of grades awarded in the May 2006 session.
Table1: Grades awarded in May 2006
Grade
A
B
C
D
E
F
Abs
Total
Number
70
126
141
84
93
48
21
583
% of Total
12.01
21.61
24.19
14.41
15.95
8.23
3.60
100%
Part 2: Comments regarding performance
2.1
General Comments
1. The level of English (both in terms of grammar and spelling) was poor and hardly up to the standard
of an examination at Advanced Level. In a number of cases, the inability of candidates to express
themselves made their answers unintelligible. Answers such as “The researcher should be covered in
wax” reflect the incomplete grasp of the rudiments of communication in English that is characteristic
of a large proportion of candidates.
2. Candidates sometimes have very detailed knowledge of human biology whereas knowledge of other
topics is often far less exhaustive.
3. Most candidates are uncomfortable with questions that require some thought and there appears to be a
general inability to apply learnt knowledge to novel situations. Candidates’ general performance in
questions that required straightforward regurgitation of memorised facts was satisfactory.
4. The majority of candidates showed a lack of understanding of basic concepts in statistics and field/
practical studies.
5. Although, essays seem to have been answered marginally better this year in comparison to past years,
some candidates still communicate in an ambiguous fashion, and find difficulty in expressing ideas
clearly using appropriate and specialist vocabulary.
6. It was evident, from answers to Question 7 in Paper 2, that inadequate importance is being given to
current issues in biology and candidates are therefore unable to relate learnt knowledge to recent
biological concerns.
7. Candidates would also be well-advised to manage their time better. A noticeable number of
candidates were clearly unable to complete the Paper 2 questions in the time allocated, due to having
written endlessly long, and not uncommonly, irrelevant answers to the first few essays.
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AM EXAMINERS’ REPORT MAY 2006
2.2
Specific Comments.
Paper 1
Question 1: Genetic inheritance
Generally candidates found it difficult to explain that a gene is also a length of DNA that codes for a
protein (and that it is the proteins that actually control phenotype in their many roles as enzymes, pumps,
transporters, motors, hormones, or structural elements). Most were able to correctly answer the question
on sex linked chromosomes. Some candidates did not describe Dihybrid inheritance with independent
assortment correctly in question 1.3. Candidates also seem to have a problem to understand the exact
meaning of epistasis (1.8) and polygenes (1.6).
Question 2: Taxonomy
Most candidates were able to correctly answer most of the questions on taxonomy and the classification
system. Candidates found some difficulty in describing a Kingdom taxonomically. The majority of
candidates were not able to suggest scientific reasons that may have encouraged taxonomists to revise
their classification of the Rock Centaury. Some candidates found a lot of difficulty to give an explanation
of a fundamental principle of this system of nomenclature.
Question 3: Animal diversity
Most candidates were able to define an animal as a eukaryotic, multicellular, heterotrophic organism.
However few candidates mentioned that animals develop from a hollow structure called a blastula. Most
candidates were able to correctly distinguish between Arachnids and Crustaceans; and between reptiles
and amphibians, although the latter two animal groups proved somewhat more difficult to be correctly
defined. Candidates found it much harder to distinguish between Hydrozoans and Scyphozoans; some
candidates mentioned totally unrelated groups while others switched the definitions. Some candidates did
not provide suitable examples.
Question 4: Cell membranes
Most candidates were able to correctly mention the importance of the cell membrane (controls how
substances can move in and out of the cell and is responsible for many other properties of the cell) and to
provide a properly labelled diagram of the cell membrane. Generally, candidates were also able to
correctly explain how steroids (Steroids are Lipid soluble – passive diffusion) and ions (protein and ion
channels) move through the cell membrane, although more candidates were unsuccessful in explaining
the latter. Most candidates were able to correctly mention and describe the endosymbiotic origin of
mitochondria and chloroplasts.
Question 5: Cell division
Most candidates overlapped / mixed up certain events of the different phases of cell division.
Question 6: Photosynthesis
Most candidates answered much of the question correctly. However it seems that quite a substantial
number of candidates have not grasped the concept of what a limiting factor is.
Question 7: Lipids
Many candidates were uncertain about the difference between lipids and fats.
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AM EXAMINERS’ REPORT MAY 2006
Question 8: Homeostasis
The first parts of the question were straightforward and were answered correctly by most candidates.
Answers to Questions 8.3 and 8.4 were not always restricted to mammals, as requested by the question.
Question 9: Rates of diffusion
The parts of the question referring to the presence of high concentration gradients were not generally
answered correctly. Other parts of the question were, in most cases, answered satisfactorily.
Paper 2
Question 1: comprehension exercise
1.1. Most candidates gave a good definition of an alien species.
1.2. This question was meant to continue the gentle introduction to the paper, yet, oddly, very few
candidates gave a correct answer to this part of the question. This manifests the typical outlook of
candidates when attempting exam questions. They overlook the simpler, more sensible answers in order
to give complicated, irrelevant facts.
1.3. Almost all candidates answered this question correctly. A number of instances were seen, however,
where parasitism was given for an answer. Clearly, candidates mixed up the relationship between the
AMFs and the tree with that of the garlic mustard. This strongly suggests that candidates would be welladvised to read questions more carefully before attempting their answers.
1.4. This part of the question was reasonably well answered. Frequently, however, candidates made
reference to the nitrogen-fixing abilities of the AMFs, clearly mistaking AMFs for the nitrogen-fixing
bacteria in root nodules, typically associated with leguminous plants.
1.5. Very few candidates gave a complete answer to this question. Several simply stated one reason as to
why they thought the effect of the garlic mustard on plants is an indirect one. It seems that some
candidates still find difficulty extracting information from the passage and using it.
1.6. Quite a good number of candidates gave a sensible, albeit not completely correct answer to this
question.
1.7. Again, candidates stopped short in their reasoning, giving only half the answer. Several limited
themselves to explaining the short-term effects of garlic mustard invasion, and little concern was given to
the long-term effects.
1.8. In many cases, this question illustrated the inadequate use of biological terms. An alarming number
of candidates referred to the fact that the plants might eventually become immune to the garlic mustard,
when in fact they meant that plants would evolve genetically to withstand the effect of toxins produced by
the garlic mustard. Few candidates mentioned competition as a factor that keeps the garlic mustard in
check in its native land.
Question 2: Analysis of data
In line with other years, this question proved to be a good discriminator, with only the better candidates
being able to score good marks. Most candidates found this question very challenging; it seems that
several candidates are reluctant to manipulate and quote data for fear of mistaking their interpretation of
it.
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AM EXAMINERS’ REPORT MAY 2006
2.1 Several candidates gave a sensible answer to this question.
2.2. The majority of candidates did not obtain full marks because they could not interpret the data
adequately. Most limited themselves to stating the obvious, namely, that endsulphate was the derivative
mostly accumulated.
2.3. Again, many candidates gave an incomplete answer to this question and could not score full marks.
2.4. A minority of candidates gave a correct answer to this part of the question.
2.5. A reasonable number of candidates gave a sensible answer although commonly, only one reason was
given.
2.6. Unfortunately, not many candidates realised that fish migrate from place to place and so they are not
very good bio-indicators of pollution of a specific location.
2.7. This part of the question gave rise to a great deal of confusion, again reflecting the poor ability of
most candidates to interpret biological data.
Section B
Some answers were very good and candidates outlined similarities and differences clearly and illustrated
their essays adequately. More commonly, however, candidates took the ‘write everything you know
about’ approach, and these were obviously unable to gain very good marks. Candidates at this level have
to demonstrate the ability to handle biological facts and to present them in the manner requested.
Question 3: Gymnosperms and Angiosperms
Reasonably good accounts were given in this essay and some excellent descriptions of the structure of the
haemoglobin molecule were seen. Some candidates need to realise the importance of drawing graphs/
diagrams to illustrate their answers.
Question 4: Respiratory pigments
Reasonably good accounts were given in this essay and some excellent descriptions of the structure of the
haemoglobin molecule were seen. Some candidates still need to realise the importance of drawing graphs/
diagrams to illustrate their answers.
Question 5: DNA analysis
Again most candidates gave reasonably good accounts in this essay, although some alarmingly poor
answers, which were often little more than general accounts of DNA structure, were also seen.
Question 6: Mechanical support
Candidates suffered in this essay due to inadequate planning. Some candidates gave long descriptions of
the structure of muscle tissue and muscular contraction (myosin-actin) which were not relevant to this
essay. Others simply listed the different structures found in the different phyla.
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AM EXAMINERS’ REPORT MAY 2006
Section C
Question 7: Immunity
A disappointingly large number of candidates had no idea how to answer this question. This is rather
alarming when considering that avian influenza is one of the major concerns of current medical science.
a) Only a minority gave a good answer to this part of the question.
b) Several realised that influenza is a viral infection and as such cannot be treated with antibiotics.
Few mentioned that antibiotics are still administered sometimes to ward off any secondary
bacterial infections that commonly follow the flu. An appalling number of candidates confuse
antibiotics for antibodies.
c) This was another question that gave rise to many poor and alarming responses. Candidates are
under the impression that taking the trivalent vaccine is better than doing nothing, at least the body
will have antibodies irrespective of the fact that they are of the wrong sort!
d) This part of the question was answered with even less confidence and very few scored marks for
this part of the question.
Question 8: General
a) Some good comprehensive answers were given for this part of the question. Not uncommonly,
however, candidates said that malaria is caused by a virus. A number of candidates are under the
false impression that sickle cell anaemia and B - thallassemia are one and the same disorder.
Some others are convinced that sickle-cell anaemia is a sex-linked disease, possibly confusing it
with haemophilia, and went through great lengths to draw genetic diagrams which were, most
obviously, wrong.
b) Some excellent answers were given to this part of the question.
c) Most candidates did not gain full marks here because they only gave half an answer.
d) Several gave vague answers about ‘ice caps melting and other such cataclysms’, with little
biological facts.
Paper 3
Question 1: Identification of carbohydrates
1.1. Most candidates mentioned were capable of suggesting at least one correct reason for grinding the
carbohydrate into a fine powder.
1.2. The majority of candidates gave a written scheme which was often incomplete. Dichotomous keys
were also presented. Otherwise, a few also gave a table explaining all the properties of each carbohydrate
mentioned.
1.3. The majority of candidates answered this question correctly.
1.4. Most candidates suggested that contamination through lack of clean apparatus as a source of error.
This is not a source of error but an inaccuracy due to the experimenter and was thus not accepted as a
correct answer.
Question 2: Mitosis in onion cells
2.1. Many candidates answered by giving the preparation of the onion epidermis cells. This shows a
failure to appreciate where mitosis occurs in a pronounced manner. Answers lacked the necessary details
such as timing, the type of stain and when applied and the type of fixative.
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AM EXAMINERS’ REPORT MAY 2006
2.2. Several candidates failed to answer correctly since they tried to explain the importance of metaphase
due to the increase in the genetic content of the onion, due to lack of cell division. Other answers such as
increased vigour, all of which were incorrect, were also given.
Question 3: Inflorescence of Wild Carrot
3.1. Some candidates failed to distinguish between the Null and Alternative Hypotheses. Others gave
answers such as t-test, showing that they lack some of the basics of statistics.
3.2. Generally a correct answer was given; sporadic errors in calculation were noted.
3.3. The majority of candidates gave the correct answer yet answers did not give the necessary details.
Numerous answers, such as “non categorical data” and “lack of standard deviation” were given (and were
often incorrect).
3.4. Candidates generally suggested a suitable statistical test although they did not always justify their
choice of test.
3.5. The majority of candidates gave the correct answer. A number of candidates could not express their
answer sufficiently clearly due to a poor standard of written English.
3.6. A large proportion of candidates answered by naming statistical tests such as Chi Square or Matched
Samples t-test rather than calculation of a correlation coefficient.
Paper 4
Question 1: Taxonomy
In 1.1, the taxonomic groups of the specimens provided were correctly identified by most students.
However, in 1.2, though the characteristics described were generally correct, sometimes these
characteristics were not diagnostic features of the phylum but of the class. Another problem was that
sometimes, the diagnostic features given were internal or otherwise not visible in the specimen provided,
while the question stated that characteristics listed should be clearly visible in the specimens.
In question 1.3 (a), when asked to comment on the probable mode of life of the specimens, some
candidates did not correlate “probable mode of life” with features visible in the specimens, but simply
gave the mode of life that they knew the specimen had. Conversely, in 1.3 (b) some candidates discussed
the mode of life, although it was not requested.
As a further point, a very common misconception is that “insects are divided into three segments”, when
in fact they consist of several segments fused into three tagmata.
Question 2: Behaviour of Littorina neritoides
2.1 Most candidates drew an appropriate table, although quite a few failed to give cumulative readings. A
substantial proportion of candidates also gave individual snails’ readings, without giving totals or
averages. A handful drew a graph instead of (or in addition to) the table, which was not required, and a
few did not include readings within the table, but rather a description of the snails’ movement.
2.2 The vast majority of candidates answered correctly, some also giving an explanation with the
description.
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AM EXAMINERS’ REPORT MAY 2006
2.3 This question is the one in which most candidates lost marks and, in fact, most candidates did not
answer correctly. A lot of candidates perceived the snails’ extensive movement in sea water as being a
result of the snail being in its natural environment and even stated that the snail was marine, rather than
saying that snails are trying to escape an unfavourable environment. In addition, a lot of candidates said
that the snails lose/gain water according to the osmotic potential, while some even said that the salts and
minerals in sea water are used by the snail to obtain energy.
Question 3: construction of dichotomous key
The construction of the dichotomous key was correct in the majority of cases, with a few who either
omitted a step or inserted an additional one. The most common mistake was the use of subjective
descriptions, such as “wide in shape”, when they should have given objective descriptions, i.e. “twice as
wide as it is long”, for example. Another common mistake was that when candidates described specimen
features, they compared one specimen to the other, for example: “the shell is longer than the others”.
Additionally, it seems that not all candidates were familiar with terms such as “whorl”, “aperture”, etc.
This was not penalised as such. However, it did mean that many of the candidates struggled with the
descriptions of the shell features, and the English used was sometimes quite unsatisfactory and
incomprehensible.
Chairperson
Board of Examiners
July 2006
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