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Q1. Figure 1 shows an animal cell and a bacterial cell.
Figure 1
(a) Compare the structure of the cells in Figure 1.
Complete the sentences.
Choose the answers from the box.
cell membrane cell wall chloroplast
cytoplasm nucleus
Only the animal cell contains a _________________________________________ .
Only the bacterial cell contains a _______________________________________ .
(2)
Figure 2 shows a section through a leaf.
Figure 2
(b) The function of palisade cells is to photosynthesise.
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Describe one way palisade cells are adapted to carry out their function.
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(1)
(c) Complete Table 1 to show whether each structure is a tissue, an organ or an organ system.
Tick one box for each structure.
Table 1
Structure Tissue Organ Organ system
Leaf
Xylem
Roots, stem and leaves
(2)
A student observed palisade cells using a microscope.
The microscope had four objective lenses, each with a different magnification.
(d) Which objective lens should the student use first?
Tick one box.
Give a reason for your answer.
×4 magnification
×10 magnification
×40 magnification
×100 magnification
Reason ____________________________________________________________
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(2)
The student measured the width of 5 different palisade cells at a total magnification of ×400
(e) Eyepiece lenses are usually ×5 or ×10 magnification.
What combination of eyepiece and objective lenses would give a total magnification
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of ×400?
Eyepiece lens ____________________
Objective lens ____________________
(1)
(f) Table 2 shows the student’s results.
Table 2
Cell Width of cell image in
mm
1 12
2 13
3 16
4 10
5 11
(f) Calculate the mean width of the palisade cell images.
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Mean width = ____________________ mm
(1)
(g) Calculate the real width of a palisade cell.
Use the mean width you calculated in part (f).
Use the equation:
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Real width = ____________________ mm
(2)
(Total 11 marks)
Q2. Coronary heart disease (CHD) is a non-communicable disease.
CHD is caused when fatty material builds up in the coronary arteries.
(a) Explain what a non-communicable disease is.
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(2)
The diagram below shows a coronary artery of someone with CHD.
(b) Explain how CHD can cause a heart attack.
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(3)
(c) Explain how lifestyle and medical risk factors increase the chance of developing CHD.
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(6)
(Total 11 marks)
Q3. Figure 1 shows the human digestive system.
Figure 1
(a) Which organ in Figure 1 produces acid?
Tick one box.
A
B
C
D
E
(1)
(b) Which organ in Figure 1 produces bile?
Tick one box.
A
B
C
D
E
(1)
(c) Where in Figure 1 are digested foods absorbed into the blood?
Tick one box.
A
B
C
D
E
(1)
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(d) Food molecules such as proteins cannot be absorbed unless they are digested.
Give one reason why.
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(1)
A scientist investigated the effect of pH on the activity of two protease enzymes.
Figure 2 shows the results.
Figure 2
(e) What is the optimum pH for enzyme Y?
pH ____________________
(1)
(f) Where in the digestive system might the two protease enzymes be produced?
Tick one box.
Enzyme X Enzyme Y
Mouth Stomach
Pancreas Mouth
Small intestine
Pancreas
Stomach Small
intestine
(1)
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Figure 3 shows a model of an enzyme molecule.
Figure 3
(g) Which substrate fits the enzyme molecule in Figure 3?
Tick one box.
(1)
(h) The enzyme and substrate diagrams are used as a model for a theory of enzyme action.
What is the name of this theory?
Tick one box.
Evolution
Lock and key
Natural selection
Protein synthesis
(1)
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(i) Explain why pH affects enzyme activity.
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(2)
(Total 10 marks)
Q4. Some diseases are communicable.
(a) What does communicable disease mean?
Tick one box.
A disease that can be spread from one person to another.
A disease that cannot be treated with antibiotics.
A disease that is not spread from animals to humans.
A disease that is passed on through genes.
(1)
(b) A woman becomes ill and has the following symptoms:
• pain when urinating
• thick yellow discharge from vagina.
Which communicable disease does the woman have?
Tick one box.
Gonorrhoea
HIV
Measles
Salmonella
(1)
Tuberculosis is a bacterial infection that affects the lungs.
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Tuberculosis causes severe discomfort.
(c) What type of medicine should be used to kill the tuberculosis bacteria?
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(1)
(d) What type of medicine should be used to treat the symptoms of TB?
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(1)
(e) Describe the ways in which the human body defends itself against the tuberculosis bacterium.
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(4)
(Total 8 marks)
Q5. The photograph below shows the lower surface of a leaf magnified 800 times.
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(a) Name hole A in the leaf surface.
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(1)
(b) Name cell B.
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(1)
(c) Cell B can lose or gain water.
Complete the sentences.
Choose answers from the box.
active
transport condensation
osmosis photosynthesis transpiration
Cell B can gain water by _______________________________ .
Water vapour can escape from the leaf through hole A
by _______________________________ .
(2)
(d) Which factors increase the rate of water loss from hole A?
Tick two boxes.
Increasing acidity
Increasing nitrogen concentration
Increasing oxygen concentration
Increasing temperature
Increasing wind speed
(2)
(e) Give one reason why the movement of water in a plant is important.
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(1)
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(f) The African Baobab tree has no leaves for up to 9 months of the year.
Suggest how this helps the tree to survive in an area where there is not much rain.
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(1)
(g) The photograph above is a photograph taken through a microscope.
The image is magnified 800 times.
One of the cells in the image has a width of 12 mm
Calculate the real width of this cell in micrometres.
Complete the following steps.
Use the equation to work out the real width of the cell in millimetres.
Real width of cell = ____________________ millimetres
Convert the real width of the cell from millimetres to micrometres.
1 millimetre = 1000 micrometres.
Real width of cell = ____________________ millimetres
(3)
(Total 11 marks)
Q6. Radioactive nuclei can emit alpha, beta or gamma radiation.
(a) Which type of radiation is the most penetrating?
Tick one box.
Alpha (α)
Beta (β)
Gamma (γ)
(1)
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(b) Which type of radiation is the most ionising?
Tick one box.
Alpha (α)
Beta (β)
Gamma (γ)
(1)
(c) Which type of radiation has the longest range in air?
Tick one box.
Alpha (α)
Beta (β)
Gamma (γ)
(1)
When radioactive isotopes in the Earth’s crust decay they release energy.
The decay causes the heating of rocks in the crust.
(d) The diagram below shows the decay of uranium-238 (U-238) into thorium-234 (Th-234).
Complete the table below to show the number of neutrons and protons in the nuclei.
Isotope Number of neutrons
Number of protons
uranium-238 146
thorium-234 90
(2)
(e) Geothermal power stations pump water through heated rocks.
The temperature of the water increases from 20 °C to its boiling point of 100 °C
Calculate the change in thermal energy when the mass of water heated is 150 kg
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Specific heat capacity = 4 200 J/kg °C
Use the Physics Equations Sheet.
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Change in thermal energy = _____________________ J
(3)
(Total 8 marks)
Q7. Figure 1 shows the label from a box containing radium-226
Radium-226 emits α, β and γ radiation.
Figure 1
(a) Figure 2 shows how the activity of the radium-226 will change.
Figure 2
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Determine the half-life of radium-226.
Show your working on Figure 2.
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Half-life = ____________________ years
(2)
(b) Radium-226 was discovered by Marie Curie in 1898.
The notebooks she used were contaminated with radium-226 and are still hazardous.
Explain why the notebooks are still hazardous.
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(2)
(c) Explain how the properties of α, β and γ radiation affect the level of the hazard at different distances.
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(6)
(Total 10 marks)
Q8. A student wanted to determine the density of the irregular shaped object shown in Figure 1
Figure 1
(a) Plan an experiment that would allow the student to determine the density of the object.
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(6)
(b) Another student did a similar experiment.
He determined the density of five common plastic materials.
Table 1 shows the results.
Table 1
Plastic material Density in kg/m3
Acrylic 1200
Nylon 1000
Polyester 1380
Polystyrene 1040
PVC 1100
Figure 2 shows the results plotted in a bar chart.
Figure 2
Complete Figure 2
You should:
• Write the correct scale on the y-axis.
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• Draw the bars for polyester, polystyrene and PVC.
(4)
(c) The student is given a piece of a different plastic material.
The student determined the density of the material three times.
Table 2 shows the results.
Table 2
Density in kg/m3
1 960
2 1120
3 1040
Determine the uncertainty in the student’s results.
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Uncertainty = _________________ kg/m3
(2)
(Total 12 marks)
Q9. Figure 1 shows solid ice on a car’s rear window.
Figure 1
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© Captive cookies/iStock/Thinkstock
The glass window contains an electrical heating element.
(a) Use the particle model in Figure 2 to describe how the heating element causes the arrangement of the ice particles to change as the ice melts.
Figure 2
You should include a description of how the particles are arranged in the solid ice and in the water.
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(6)
(b) A car manufacturer tests different heating elements by measuring how long it takes ice to melt.
During the test some variables must be controlled.
Identify two control variables in the car manufacturer’s test.
Tick two boxes.
The colour of the car
The current in the heating element
The mass of ice
The size of the car
The time taken for the ice to melt
(2)
(c) Some of the energy supplied by the heater causes the ice to melt without the temperature of the ice increasing.
What is the name given to this energy supplied by the heater?
Tick one box.
Latent heat of freezing
Latent heat of fusion
Latent heat of vaporisation
(1)
(d) When the heater is supplied with 120 J of energy each second, the internal energy of the ice increases by 45 J each second.
Use the following equation to calculate the efficiency of the heater.
Efficiency =
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Give your answer to two decimal places.
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Efficiency = ____________________
(2)
(Total 11 marks)
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Mark schemes
Q1. (a) nucleus
1
cell wall 1
(b) any one from:
• contain (many) chloroplasts
• positioned near the top surface of the leaf
• packed closely together 1
(c)
Structure Tissue Organ Organ system
Leaf ✔
Xylem ✔
Roots, stem and leaves
✔
additional tick in a row negates the credit for that row
allow 1 mark for two correct rows 2
(d) ×4 1
reason: any one from:
• gives the largest field of view
• easier to focus 1
(e) eyepiece lens: ×10 and objective lens: ×40
or
eyepiece lens: ×5 and objective lens: ×80
allow sensible suggestions that give a magnification of ×400 1
(f) 12.4 (mm)
allow 12 (mm) 1
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(e) real width = 1
0.031 (mm)
an answer of 0.031 (mm) scores 2 marks
allow ecf from part (f) 1
[11]
Q2. (a) is not caused by a pathogen / infective organism
allow not caused by a microorganism / microbe ignore not caused by infection
ignore named pathogen unless bacteria, virus and fungus all mentioned
1
(so) is not passed / spread (from person to person)
allow cannot be spread / caught allow is not infectious / contagious
1
(b) reduced / restricted / stopped blood flow
it does not matter where blood flow is restricted to − heart / body
1
(so) less oxygen reaches heart (muscle / cells)
must reference heart / it allow no oxygen reaches the heart (muscle / cells)
1
(so heart muscle / cells) cannot respire (enough)
or (so heart muscle / cells) do not release (enough) energy
do not accept do not make / produce / create energy
ignore references to breathing / suffocation
ignore blood clots / blockages 1
allow ‘it’ for heart
(c) Level 3: Relevant points (factors / effects) are identified, given in detail and logically linked to form a clear account.
5−6
Level 2: Relevant points (factors / effects) are identified and there are attempts at logical linking. The resulting account is not fully clear.
3−4
Level 1: Points are identified and stated simply, but their relevance is not clear and there is no attempt at logical linking.
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1−2
No relevant content 0
Indicative content
medical risk factors: • high blood pressure • high cholesterol • diabetes • genetic factors • medications
lifestyle risk factors: • smoking • obesity • lack of exercise • high fat / energy diet • eating insufficient fruit / vegetables • alcohol • high salt intake • exposure to air pollution • certain drugs / correct named drug
examples of links: • smoking − high bp / cholesterol / fatty deposition • obesity − lack of exercise / high bp / cholesterol / fatty deposition /
diabetes • exercise − obesity / bp /diabetes • diet − obesity / cholesterol / diabetes • alcohol − bp / cholesterol • high salt intake − high blood pressure • genetic factors − bp / cholesterol / diabetes / obesity • medication − can affect blood / blood vessels / metabolism
the main discriminator is the quality of linking both lifestyle and medical factors are required for level 3
[11]
Q3. (a) C
1
(b) B 1
(c) E 1
(d) any one from:
• they are too big
• they are insoluble 1
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(e) (pH) 7.5
allow answers in range 7.4 to 7.6 1
(f) (enzyme X) stomach
(enzyme Y) small intestine 1
(g) 1
(h) lock and key 1
(i) (some pH values):
change the shape of the active site
allow some pH values denature enzymes 1
(so) so substrate will no longer fit / bind to the active site 1
[10]
Q4. (a) a disease that can be spread from one person to another
1
(b) gonorrhoea 1
(c) antibiotics 1
(d) painkillers
allow aspirin, paracetamol, ibuprofen and other correct brand names
1
(e)
Level 2: Scientifically relevant facts, events or processes are identified and given in detail to form an accurate account.
3-4
Level 1: Facts, events or processes are identified and simply stated but their relevance is not clear.
1-2
No relevant content 0
Indicative content
• skin stops the bacterium (entering the body)
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• blood clots to stop bacteria entering (through cuts)
• stomach acid will kill the bacterium (if it is in food)
• nose / trachea have mucus to trap the (tuberculosis) bacteria
• nose / trachea have cilia / hair to move mucus out
• white blood cells destroy the bacteria if infected
• by phagocytosis
• by antibodies
• by antitoxins
4
[8]
Q5. (a) stoma / stomata
ignore pore 1
(b) guard (cell) 1
(c) osmosis
in this order only 1
transpiration 1
(d) increasing temperature 1
increasing wind speed 1
(e) any one from: • for photosynthesis • to bring mineral (ions) into / up the plant
allow correctly named ions e.g. nitrates
• translocation
allow to cool the plant 1
(f) any one from: • decreased transpiration
allow no transpiration
• less water lost
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allow no water lost 1
(g) 1
0.015 (millimetres) 1
15 (micrometres)
allow 1 mark for incorrect width × 1000 1
an answer of 15 (micrometres) scores 3 marks
[11]
Q6. (a) gamma
1
(b) alpha 1
(c) gamma 1
(d)
isotope number of neutrons
number of protons
uranium-238 146 92 1
thorium-234 144 90 1
(e) Δθ = 80 °C 1
E = 150 × 4200 × 80 1
E = 50 400 000 (J)
allow 50 000 000 (J) 1
allow max 2 marks for correct calculation using incorrect value of Δθ
allow 1 mark for correct calculation using θ = 20 or θ = 100
an answer of 50 400 000 scores 3 marks
[8]
Q7. (a) horizontal line drawn from
92 000 Bq
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allow 90 000–94 000 1
1600 years
allow 1500–1700 1
(b) only (119) years have passed 1
activity has not dropped by much 1
(c)
Level 3: Relevant points (reasons/causes) are identified, given in detail and logically linked to form a clear account.
5-6
Level 2: Relevant points (reasons/causes) are identified, and there are attempts at logically linking. The resulting account is not fully clear.
3-4
Level 1: Points are identified and stated simply, but their relevance is not clear and there is no attempt at logical linking.
1-2
No relevant content 0
Indicative content
properties
• alpha is the least penetrating
• alpha is the most ionising
• alpha has least range in air
• beta is the second most penetrating
• beta is the second most ionising
• beta has the second longest range in air
• gamma is the most penetrating
• gamma is the least ionising
• gamma has the greatest range in air
hazard (linked to correct property)
• short-range alpha most dangerous
• mid-range beta most dangerous
• long range gamma most dangerous
6
[10]
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Q8. (a) Level 3: The method would lead to the production of a valid outcome. All key
steps are identified and logically sequenced. 5−6
Level 2: The method would not necessarily lead to a valid outcome. Most steps are identified, but the method is not fully logically sequenced.
3−4
Level 1: The method would not lead to a valid outcome. Some relevant steps are identified, but links are not made clear.
1−2
No relevant content 0
Indicative content
• measure mass • use a top pan balance or scales
• part fill a measuring cylinder with water • measure initial volume • place object in water • measure final volume • volume of object = final volume − initial volume
• fill a displacement / eureka can with water • water level with spout • place object in water • collect displaced water • measuring cylinder used to determine volume of displaced water
• use of:
(b) all y-axis values correct (minimum of 3)
allow 1 mark for two correct values 2
all bars drawn to the correct height
allow 1 mark for two correct bars allow ± ½ small square
2
(c)
ignore + and / or − signs 1
= 80 (kg/m3)
an answer of 160 scores 1 mark 1
an answer of 80 scores 2 marks
[12]
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Q9. (a) Level 3 (5–6 marks):
A clear, logical explanation containing accurate ideas presented in the correct order with links between ideas.
Level 2 (3–4 marks): Key ideas presented with some linked together to form a partial explanation.
Level 1 (1–2 marks): Fragmented ideas, some may be relevant, insufficient links to form an explanation.
0 marks: No relevant content.
Indicative content • current in the wire causes heating • increases temperature of the metal wires / ice
Solid • arrangement of particles is regular • particles vibrate about a fixed position
Melting • internal energy of the ice increases, increasing the temperature to
melting point
• so (as the temperature increases) particles vibrate faster • eventually particles vibrate fast enough to break free from the (strong)
bonds • therefore the arrangement of particles becomes irregular
Liquid • arrangement of particles is irregular • particles movement (translational) is random
6
(b) The current in the heating element 1
The mass of ice 1
(c) latent heat of fusion 1
45 / 120 = 0.375 1
0.38
allow 0.38 with no working shown for 2 marks
allow 0.375 with no working shown for 1 mark 1
[11]
