CJ*(W10-239-02)
ADDITIONAL MATERIALS
In addition to this paper you may require a calculator and a ruler.
INSTRUCTIONS TO CANDIDATES
Write your name, centre number and candidate number in the spaces at the top of this page.
Answer all questions.
Write your answers in the spaces provided in this booklet.
INFORMATION FOR CANDIDATES
The number of marks is given in brackets at the end of each question or part-question.
You are reminded of the necessity for good English and orderly presentation in your answers.
GCSE 239/02
ADDITIONAL SCIENCE
HIGHER TIER BIOLOGY 2
A.M. THURSDAY, 14 January 2010 45 minutes
For Examiner’s use only Question Max.
Mark
Mark Awarded 1
2 3 4 5 6 7 8 9 Total
8 5 6 6 5 5 5 4 6 50 Candidate
Name
Candidate Number Centre
Number
0
W10 239 02 1
(239-02)
pH 2 3 4 5 6 7
Enzyme A 2.6 7.9 4.1 2.3 1.1 0.8
Enzyme B 0.0 0.0 0.3 1.2 2.4 3.7 Rate of reaction
/arbitrary units
(a) Complete the chart below by plotting the data for enzyme A. Join the plots with a ruler.
The data for enzyme B has been plotted for you. [3]
Enzyme B
0 1 2 3 4
2 3 4 5 6 7
5 6 7 8
pH
Rate of reaction / arbitrary units
Examiner
Answer all questions. only
1. Thomas and Rhiannon set up an experiment to discover the effect of pH on the rate of reaction of two protease enzymes A and B.
The time taken for the complete digestion of a protein was measured at six different pH values ranging from pH 2 to pH 7.
The results are shown in the table below.
Turn over.
(239-02) 8
(b) At which pH is the rate of reaction the same for both enzymes? [1]
. . . .
(c) Describe the effect of pH on the rate of reaction of enzyme A. [2]
. . . .
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. . . .
(d) Thomas and Rhiannon decided to repeat the experiment with a sample of enzyme A which had been boiled and cooled.
(i) What effect would this enzyme have on the digestion of protein? [1]
. . . .
(ii) Explain your answer. [1]
. . . .
3 Examiner
only
W10 239 02 3
(239-02)
2. The photograph below shows illegal loggers clearing a forest in Borneo, Indonesia.
The land is being cleared for the agricultural production of palm oil.
Palm oil is used to produce bio-fuels, and foods such as crisps, peanut butter and oven chips.
Source: WWF - Canon/Alain Compost
The maps below show the forested areas of the island of Borneo in 1930, 1999 and 2004.
Forests Key:
Orangutan foundation UK
Hugo Ahlenius, UNEP The orangutan lives in the forests of Borneo.
Examiner only
Turn over.
(239-02) 5
(a) Read the following facts and answer the questions that follow.
Since 1930
• there has been a great increase in the number of people living on earth
• there has been very little increase in the number of people living in Borneo
• the number of orangutan living in Borneo has rapidly decreased
(i) Explain how the increase in the number of people living on earth has resulted in the
decrease in the number of orangutan. [2]
. . . .
. . . .
. . . .
. . . .
(ii) In the 69 years between 1930 and 1999 the area occupied by orangutans in Borneo halved. It halved again in the 5 years between 1999 and 2004. From this evidence,
suggest how the map might look in 2030. [1]
. . . .
(iii) How could the people living in other countries, outside Borneo, help stop the decrease
in the numbers of orangutan? [1]
. . . .
(b) Apart from agriculture suggest one other reason why forests are cleared. [1]
. . . .
5 Examiner
only
W10 239 02 5
6
(239-02)
3. The diagram below shows the human digestive system.
(a) Label the parts A and B on the diagram. [2]
(b) Describe the digestion in the small intestine of a meal containing carbohydrate, protein and
fat. [4]
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A. . . .
B. . . .
Examiner only
7
BLANK PAGE
Turn over.
W10 239 02 7
(239-02)
4. (a) (i) Complete the word equation for photosynthesis. [1]
carbon dioxide + . . . . glucose + . . . .
(ii) Other than starch production, state two uses made by the plant of the glucose made in
photosynthesis. [1]
. . . .
. . . .
(b) The amount of starch and glucose in the leaves of a plant were measured over a 24 hour period. The results are shown in the graph below.
(i) State the relationship between starch production and light intensity. [1]
. . . .
. . . .
. . . .
(ii) Explain why
I. the level of starch is lowest between midnight and 4 am. [1]
. . . .
II. the level of glucose is lowest at 12 noon. [1]
. . . .
(iii) Using the information in the graph, state the time you would expect to find the lowest concentration of carbon dioxide in the air at the surface of the leaf. [1]
. . . . 6
0 10 20 30
4am
Midnight
5 15 25 35
8am 12 Noon 4pm 8pm Midnight
Glucose
Starch Light intensity increasing Light intensity decreasing
Glucose and starch content / arbitrary units
Examiner only
(239-02) Turn over.
5. A lake that was very popular with fishermen became infested with mosquitoes.
It was sprayed with an insecticide each year for several years.
After this time, many dead fish-eating birds were found near the lake.
Biologists sampled a variety of organisms from the lake and tested them for concentrations of insecticide.
The table shows the results.
Organism Mass of insecticide per unit body mass Plant plankton
Small fish Large fish Fish-eating birds
0.04 0.23 2.80 75.50
(a) Explain the presence of the dead fish-eating birds. [2]
. . . .
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(b) Conservationists wanted to introduce either herbivorous beavers or carnivorous otters into the lake to increase biodiversity.
(i) What does biodiversity mean? [1]
. . . .
. . . .
(ii) Give two reasons why introducing beavers rather than otters might be a good idea. [2]
(I) . . . . . . . .
. . . .
(II) . . . . . . . .
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5
9 Examiner
only
(239-02)
6. Muscle tissue is made of dark coloured and light coloured cells. The graph below shows the percentage of dark coloured cells and of light coloured cells found in muscles of different types of athletes.
0 20 40 50 90 100
sprinters
10 30 60 70 80
shot putters weight lifters 800m runners javelin throwers cyclists orienteers 5000m runners swimmers marathon runners
light coloured cells
dark coloured cells Key:
cells / %
The dark coloured cells have to use oxygen for releasing energy.
The light coloured cells do not have to use oxygen for releasing energy.
(a) A sample of muscle cells from a person was examined and the number of light coloured cells was counted. The results showed that in a sample of 320 cells, 80 were light coloured.
(i) Calculate the percentage of light coloured cells. [1]
. . . .% (ii) Using the graph above, state which type of athlete gave the sample of muscle. [1]
. . . .
Examiner only
(239-02) Turn over. 5 (iii) What does the graph tell you about the difference between the type of respiration in
the muscle cells of a swimmer and a weight lifter? [1]
. . . .
. . . .
. . . .
(iv) Which of the ten different types of athletes would produce most lactic acid in the
muscle cells? [1]
. . . .
(b) Explain how a good blood supply helps to prevent an oxygen debt. [1]
. . . .
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11 Examiner
only
7. In order to investigate how molecules pass through cell membranes, a student carried out the following procedure.
A freshly laid hen’s egg was placed in a beaker and covered with dilute hydrochloric acid. It was left for 12 hours.
After this time it was found that the egg shell had dissolved in the acid, leaving the egg surrounded by a membrane which acts like a cell membrane.
The egg was removed from the dilute acid and placed in a beaker of water.
After one hour the egg was much larger than before.
(239-02)
egg egg
dilute hydrochloric
acid
shell and
cell membrane cell
membrane
egg egg
water
cell membrane
After 12 hours
After 1 hour
Examiner only
(239-02) 5 Turn over.
(a) Explain how the egg became larger. [4]
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(b) Frogs lay eggs in fresh water. Their eggs do not have shells but they do have membranes surrounding them.
Suggest why frogs never lay eggs in sea water. [1]
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13 Examiner
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(239-02) 4 8. The table shows the energy balance for intensive (indoors) and open range (outdoors) meat
production from cattle.
Indoors 10 000
6 000 0.25
Outdoors 5 950
50 0.03 Energy input as food
Energy input as fossil fuel Efficiency / %
Energy / kJ per m2per year
(a) Use the data and your knowledge to explain why it is more efficient to produce meat from
cattle indoors than outdoors. [2]
. . . .
. . . .
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(b) Suggest two ways in which a farmer uses fossil fuel as energy input. [2]
(i) . . . .
(ii) . . . .
Examiner only
(239-02) 6 9. The kudzu vine (Pueraria montana) is one of the fastest growing flowering plants in the world. It
was introduced from Japan to the U.S.A. in 1876 and has spread to become a pest.
The kudzu vine has bacteria in its roots which change nitrogen from the air into nitrates which are transported to its leaves.
Its leaves contain twice as much nitrate as the leaves of other plants.
Its leaves often fall into lakes or on soil near lakes.
Adapted from New Scientist, August 2007
(a) What name is given to an unwanted species which is introduced from another part of the
world where it normally lives? [1]
. . . .
(b) Explain how and why the kudzu vine could be a problem to fish populations where it grows
in the U.S.A. [5]
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15 Examiner
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