AGRICULTURE GCE Ordinary Level

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AGRICULTURE
GCE Ordinary Level
Paper 5038/01
Paper 1
General comments
For many Centres, this was the first examination in this format, so it was good to see that there were very
few rubric infringements by candidates. Most seemed to have had no problems in completing the paper in
the time allowed and the standard achieved by some candidates was very high. There tended to be a
weakness in answering questions requiring application of knowledge rather than straightforward recall of
facts. At times, candidates appeared to have preconceived ideas about what an answer must be. The
examination tests candidates’ ability to apply information but there are no questions which deliberately
attempt to trick candidates. They should read questions carefully and establish exactly what is being asked.
Comments on specific questions
Section A
Question 1
(a)(i)
(ii)
Structures A, B and C were plumule, radicle and cotyledon, respectively. Common errors were to
confuse A and B and name C as the testa, which is clearly a separate structure on the diagram.
The main function of C, in this type of seed, is to store the nutrients required for germination.
Reference to the role of the cotyledons in protecting the embryo was accepted but not protecting
the seed.
(b)
Many candidates thought that light is a universal requirement for germination. Whilst it is needed
by some seeds, this is not the case for most. Water, air and a suitable temperature are the
requirements. Many candidates referred to “humidity”, which is not an acceptable alternative to
“water”. “Temperature” alone is not sufficient but must be qualified as shown above or described
as warmth.
(c)
Very few candidates gained any marks here. Candidates should realise that the presence or
absence of nutrients will not affect germination, as the seed has the nutrient requirements within
itself. Cultivation of the soil to provide a fine tilth, which then allows the presence of the necessary
conditions for germination, was the point that was looked for. One or two candidates made a valid
point about the surface of the soil being hard in uncultivated ground, preventing seedlings form
emerging and others referred to the competitive presence of weeds but competition for nutrients in
this context was not accepted.
Question 2
(a)(i)(ii) Most candidates labelled the structures correctly. Common errors were to label the pancreas as
the liver and the large intestine as the small intestine. A few labelled the stomach as S, perhaps
assuming that this was what the letter signified. Candidates mentioned the role of the small
intestine in completing digestion and many also referred to the absorption of digested materials into
the blood. A number suggested absorption of water here. This was not accepted as this occurs
mainly in the large intestine.
(b)
Crop and gizzard were the obvious correct answers. Vent was also accepted as was
proventriculus, although this could be equated to the stomach. A number of candidates confused
structures found in a ruminant with those in a chicken, naming rumen, reticulum etc.
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(c)(i)(ii) This was well answered, the most common responses being calcium and iron, with appropriate
uses. A named mineral, with a specific function was expected so “salt” was insufficient for a mark.
The term mineral was not understood by some candidates who suggested “protein”, “fat”, or
“carbohydrate”. These were the constituents expected in (ii), with water as an alternative.
Question 3
(a)(i)(ii) Many candidates seemed to believe that the soil with large particles must have all the “good”
properties and the one with small particles be all “bad”. Hence, there were answers, which
included “easily leached” and “retains nutrients” in the same column. While many candidates
suggested the addition of lime (to flocculate clay particles) or organic matter, adding sand was also
a common suggestion. This is not an effective method of soil improvement and was not accepted.
(b)(i)
(ii)(iii)
The pH shown on the meter was 5; this would show as orange with liquid indicator. Soil with this
pH would be acid. This was generally well answered but some candidates were unsure about
which pH levels are acid and which alkaline, attempting to give noncommittal answers to (iii), such
as “it tells the acidity or alkalinity”.
(c)(i)(ii) Few candidates gave correct answers here. It was expected that, having noted that the pH was 5,
candidates would use the graphs and see that iron was most readily available. Adding lime to a
soil will raise its pH, so that iron will then become less available, once pH 7 is passed, but nitrogen
and calcium will become more available. Candidates seemed unable to apply their knowledge and
extrapolate this level of detail from the information given.
Question 4
(a)(i)(ii) A, B and C were carbon dioxide, oxygen and water, respectively. Some candidates confused A
and B and some suggested “light” for A but this is not a “substance” so was not accepted. Some
candidates attempted to name parts of a leaf, suggesting that they had either not read or not
understood the question. Whilst many candidates were able to label the inner part of the vascular
bundle (the xylem) some seemed to think that the answer must be “cambium”, possibly because
they were asked to use a C.
(b)(i)(ii) Many candidates gave an excellent definition, referring to the products of photosynthesis and
naming the tissue, correctly, as the phloem.
The question, as a whole, produced a good number of maximum marks.
Question 5
For many Centres this would be the first time that genetics has been tested on this syllabus. Clearly, some
candidates had no knowledge of this area but others produced excellent answers.
(a)(i)
(ii)(iii)
(iv)
The two genotypes were yy and Yy, respectively. The cross should then have used these two,
with the resulting offspring being yy and Yy, in equal proportion. Some candidates gave correct
answers to (i) and (ii) but then gave the cross as yy x YY. This suggests that they had not read the
question carefully. The phenotypes were yellow and white if the correct cross was made but
candidates were credited with the mark if their answer was correct in terms of the cross that they
had used in (iii) or where they had stated that phenotype refers to the external appearance of the
plant.
(b)(i)(ii) This was badly answered by the majority of candidates. Few could define livestock improvement.
(iii)
Methods of carrying this out were often given as improving housing or feeding, rather than aspects
of breeding, such as introducing new breeds or the use of artificial insemination. Consequently,
there were few relevant suggestions for problems that keeping improved livestock might produce.
Points looked for were the expense of suitable feed for such animals, their possible increased
susceptibility to disease or the inability of exotic breeds to withstand local conditions.
Question 6
Candidates were asked to give a different answer for each material but this was ignored in a number of
cases. “Brick is more durable but wood is less durable” will gain only one mark. Candidates should try to be
more specific, mentioning factors such as wood rotting or being damaged by termites. Using cost of
materials for each of the three parts of the building was also penalised. Candidates should have sufficient
knowledge of the properties of the materials to give more varied answers.
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Question 7
(a)
Some candidates were very well-informed about the working of the four stroke engine and gained
full marks whilst others based their answers on guesses, rather than knowledge. The correct
completion of the three columns was: closed, closed, upwards; closed, closed, downwards; closed,
open, upwards.
(b)
Most candidates were able to give good answers here, mentioning, most commonly, speed, power
and low labour input as advantages. Cost, soil compaction and unemployment were the commonly
stated disadvantages. Simply stating that “it needs maintenance” or “cannot be used when broken”
is too vague, as these could be applied to hand tools and implements pulled by animals.
Section B
Question 8
(a)(i)(ii) There were many excellent answers to this question, with clear well-labelled diagrams. The reason
for the shape of the wall (wider at the base) was the most commonly omitted point, but many
candidates gained maximum marks for this section.
(b)(i)
Candidates named a method of irrigation correctly but descriptions were not always clear. Some
candidates included a simple, labelled diagram, which was effective in clarifying their answers.
(ii)
Some candidates misread the question as the advantages of the specific method of irrigation that
they had named, whereas more general advantages were looked for. These could have included
improved quality and yield and higher prices for scarce commodities which could be grown out of
season (in the dry season, for example).
Question 9
(a)
Almost all candidates named the type of livestock, as required by the question. This meant that
points such as checking the state of the udders and the milk (for mastitis) could be accepted where
the livestock was named as a cow. Most candidates had a good knowledge of general signs, such
as discharges from eyes, nose and mouth, condition of coat and faeces, temperature and
behaviour.
(b)(i)(ii) Answers here should have been relevant to the livestock named in (a). Where this was ignored,
(iii)
the parasite named was not always appropriate. Some candidates confused the tick (as a
parasite) with the disease that it transmits, naming the disease as the parasite and describing
methods of control, in terms of drugs, for this. The tick was a commonly named parasite but the
damage caused was often confined to transmission of disease, with infrequent mention of damage
to the skin or the potential for anaemia. Few candidates mentioned rotational grazing as a means
of control and many do not know that the generic term for the chemicals used in dips and spray
races is acaricide.
(c)
Candidates should have been able to list nutrient deficiency, bacteria, viruses and fungi as causes
of animal disease. Whilst many candidates mentioned poor nutrition, few referred to pathogenic
organisms. Bad housing or lack of hygiene were commonly mentioned. They do not, in
themselves, cause disease, although they may provide the conditions under which attack by
pathogens is more likely.
Question 10
(a)(i)
(ii)
Almost all candidates named a crop. Conditions required by that crop should be detailed. “A warm
temperature” or “a lot of rain” are too vague. Reference to range, quantity or seasonal distribution
is needed. Most candidates were more precise about soil requirements, describing texture and pH.
There were good accounts of spacing details and fertiliser requirements but soil preparation was
described less thoroughly. Candidates invariably mentioned clearing weeds and stones but did not
give much detail of cultivations needed to get the soil into condition for sowing.
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(b)(i)(ii) The question required a pest or disease to be named. Candidates should follow instructions as
(iii)
extra marks were not gained for mentioning both or for listing several pests, as some candidates
did. Indeed, marks may, ultimately, have been lost, as the accounts of effects and controls
became confused and it was difficult to establish which effect or control related to which pest or
disease. Candidates should also avoid giving lists of general controls, which may not be relevant
to the organism named. For example, crop rotation is not effective for flying insect pests.
Question 11
(a)
This question was answered by many candidates who showed poor knowledge and understanding
of the topic. Some candidates were not clear about the difference between intensive and extensive
grazing and showed little understanding of the advantages and disadvantages of extensive
systems. Lower expenditure (no fencing required) and less labour should have been obvious
advantages. Many candidates mentioned difficulties of “control” as a disadvantage but failed to
state what should be controlled, such as breeding or soil erosion. “More disease” is also too
vague. There should have been reference to difficulties in checking for disease. Problems of
selective grazing and overgrazing were common correct points and a few candidates mentioned
that cattle wasted energy in moving over large distances, so would be less productive.
(b)
Descriptions were poor, with little detail. The best were generally of zero grazing but those
describing rotational grazing could have made much better use of annotated diagrams to explain
their answers.
(c)
Methods of pasture improvement were not well known. Avoiding overstocking and controlling
grazing were accepted but many candidates failed to mention any other obvious points, such as
use of fertilisers and irrigation, re-seeding with improved grasses, introducing legumes and weed
control.
Question 12
(a)
It was pleasing to note that candidates kept to the point and answered the question set with
concise and relevant points, as this type of question often attracts weaker candidates who are
struggling to find a third question to answer. Candidates were well aware of the importance of
agriculture beyond provision of food, mentioning employment, raw materials for industries and
products for export, with good examples, particularly of the last two.
(b)
Answers here centred on lack of capital, with the consequences of this in terms of lack of inputs,
machinery, etc. Inadequate knowledge and conflicts of land usage were well-made points.
(c)
Some candidates answered in terms of government agencies providing means and capital for
development of enterprises by farmers, which is not research. Research involves the scientific
development of new techniques, better varieties of crops and livestock and better control of pests
and diseases. Examples of biotechnology, including genetic modification, were mentioned in good
answers.
Paper 5038/03
Practical
General comments
All candidates attempted all parts of every question – indicating that there was sufficient time allocated for
the examination. There were no cases of candidates infringing the examination rubric.
It would be useful if more candidates were fully aware of examination technique with regard to taking account
of the mark allocation for each question in their responses. Again, some candidates continue to provide
responses for practical questions by stating what they thought should be the outcome, as opposed to
describing their actual observations.
No Centres described any difficulties in providing the necessary apparatus or reagents.
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Comments on specific questions
Question 1
(a)(i)
There was a great range in the quality of drawings provided by candidates. The range was from
inadequate sketches to acceptable line diagrams. Despite the instructions in the question, some
candidates labelled the diagram. Invariably this was unnecessary, because the standard of the
diagram was sufficient or, if not, the labels did not identify correctly structures that were visible on
the underside of a leaf.
(ii)
Nearly all candidates described the difference in colour between the upper and lower surface of a
leaf. Most described the presence/absence of hairs or stoma. A minority of candidates stated that
they were able to observe structures that would not be visible using a hand lens.
(b)(i)
Many candidates described changes to the leaf that do not occur if the leaf is heated in hot water.
For instance, some candidates stated that the leaf had become brittle or had been bleached –
implying that they had not been completing the questions during the experiment or that they had
not done the experiment and were attempting to answer the question by recall.
(ii)
Candidates who made a correct response to the previous section, invariably answered this section
of the question correctly.
(iii)
Generally the results table was completed correctly. However, there is evidence that some
candidates might not have performed the experiment at all, because they provided responses
associated with a Benedict’s test rather than the Iodine test.
(iv)
This question was marked based on the responses in the results table i.e. candidates were not
doubly penalised if they had made a mistake with their practical technique
(v)
The most common response was that one of the leaves had been deprived of light. Very few
candidates were able to suggest a second reason why photosynthesis had not occurred. Despite
the leaves being green, the absence of chlorophyll was a frequent incorrect response.
(vi)
This question was not answered well. The best answers involved processes to avoid scalding.
Too many candidates described safety precautions that were not relevant to the experiment.
Question 2
(a)
Most candidates were able to cut the card shape and measure the diagonal distance accurately. It
was clear that some candidates decided to measure the distance on the diagram, which was not
correct.
(b)(i)
Most candidates were able to draw around the card and label ABCD. There were relatively few
candidates who had made their pinholes within the required distance from the upper corners. The
labels Y and Z were in the correct position on the diagrams of most candidates.
(ii)
Nearly all candidates who were able to draw around the card correctly were able to determine its
centre of gravity.
(iii)
This question was not answered well. The most common incorrect response involved suspending
the card from different points, something that would have no effect on the centre of gravity.
Question 3
(a)
This question was answered well. The standard of diagrams from candidates was commendable.
A few candidates did not wait long enough for the soil sample to settle. Some candidates were
inconsistent in their shading and labelling of their diagrams, the most common oversight was to
draw the floating organic matter, but not label it.
(b)
Many candidates were able to suggest properties of the soil, but were unable to provide reasons.
Consequently, credit for suggesting a suitable property was given irrespective of under which
heading the suggestion appeared.
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