Q1. The diagram shows four ways

Q1.
The diagram shows four ways in which molecules may move into a cell and out of a cell.
The dots show the concentration of molecules.
The cell is respiring aerobically.
Write the correct letter, A, B, C or D, next to each process.
Process
Arrow
A, B, C or D
The movement of oxygen molecules
The movement of carbon dioxide molecules
The active uptake of glucose molecules
(Total 3 marks)
Page 1 of 55
Q2.
(a) The concentration of sulfate ions was measured in the roots of barley plants and in the
water in the surrounding soil.
The table shows the results.
Concentration of sulfate ions in mmol per
dm3
Roots of barley plants
1.4
Soil
0.15
Is it possible for the barley roots to take up sulfate ions from the soil by diffusion?
Draw a ring around your answer. Yes / No
Explain your answer.
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(2)
Page 2 of 55
(b)
Some scientists investigated the amounts of sulfate ions taken up by barley roots in the
presence of oxygen and when no oxygen was present.
The graph below shows the results.
(i)
The graph shows that the rate of sulfate ion uptake between 100 and 200 minutes,
without oxygen, was 0.4 arbitrary units per minute.
The rate of sulfate ion uptake between 100 and 200 minutes, with oxygen, was
greater.
How much greater was it? Show clearly how you work out your answer.
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Answer ..................... arbitrary units
(2)
Page 3 of 55
(ii)
The barley roots were able to take up more sulfate ions with oxygen than without
oxygen.
Explain how.
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(3)
(Total 7 marks)
Q3.
Plants need chemical energy for respiration and for active transport.
(i)
Write a balanced chemical equation which represents the process of respiration in plants.
.....................................................................................................................................
(2)
(ii)
Describe the process of active transport in the root hair cells of plants.
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(3)
(Total 5 marks)
Page 4 of 55
Q4.
The diagram shows a section through the chest.
For each question write the correct letter in the box.
Which structure, A, B, C or D, is:
(a)
a rib
(1)
(b)
the diaphragm
(1)
(c)
an alveolus?
(1)
(d)
Complete the following sentences.
(i)
When we breathe in the rib cage moves ...................... and the diaphragm
becomes ...................... .
(2)
(ii)
Alveoli are adapted for absorbing ........................................................ .
(1)
(Total 6 marks)
Page 5 of 55
Q5.
Emphysema is a lung disease.
(a)
The drawings show sections through the lung of a healthy person and through the lung of a
person with emphysema. The drawings are drawn to the same scale.
Use information from the drawings to answer the questions.
What effect does emphysema have on:
(i)
the thickness of the surface used for gas exchange
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...........................................................................................................................
(1)
(ii)
the total area available for gas exchange?
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(1)
Page 6 of 55
(b)
Two men did the same amount of exercise.
One man was in good health. The other man had emphysema.
The results are shown in the table.
Man with
good health
Man with
emphysema
Oxygen entering blood in dm3 per minute
2.1
1.1
Air flow into lungs in dm3 per minute
90.7
46.0
The man in good health was able to take more oxygen into his blood than the man with
emphysema.
Calculate how much more oxygen was taken into the blood per minute by the man in good
health. Show your working.
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Answer = ....................................................... dm3 per minute
(2)
(Total 4 marks)
Page 7 of 55
Q6.
The diagram shows a small part of a lung.
(a)
The arrow on the diagram shows the movement of oxygen from the air in the alveolus to
cell X.
Complete the sentences by drawing a ring around the correct answer.
platelet
(i)
Cell X is a
red cell
white cell
(1)
diffusion
(ii)
Oxygen moves from the air in the alveolus into cell X by
filtration
respiration
(1)
glycogen
(iii)
The substance in cell X that combines with oxygen is called
haemoglobin
lactic acid
(1)
Page 8 of 55
a cell membrane
(iv)
Cell X does not have
cytoplasm
a nucleus
(1)
(b)
On the diagram, draw an arrow to show the movement of carbon dioxide during gas
exchange.
(1)
(Total 5 marks)
Q7.
The small intestine is lined with millions of villi.
The diagram shows the structure of a villus.
In the small intestine, some of the products of digestion are absorbed into the blood by active
transport.
(a)
Explain what is meant by active transport.
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(2)
Page 9 of 55
(b)
How do microvilli and mitochondria help in the active transport of the products of digestion
from the small intestine into the blood?
Microvilli ....................................................................................................................
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Mitochondria ..............................................................................................................
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(2)
(Total 4 marks)
Q8.
Diagram 1 shows two villi in the small intestine of a healthy person.
(a)
Describe two features of the villi which help the small intestine to function.
1 .................................................................................................................................
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2 .................................................................................................................................
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(2)
(b)
Diagram 2 shows two villi in the small intestine of a person with coeliac disease.
Page 10 of 55
(i)
How do the villi of the person with coeliac disease differ from those of a healthy
person?
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(1)
(ii)
Suggest how this difference might affect how well the small intestine functions.
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(1)
(Total 4 marks)
Q9.
(a)
The diagram shows a cereal crop.
Complete spaces (i) and (ii).
(2)
(iii)
What sort of weather may cause the cereal crop to wilt?
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(1)
Page 11 of 55
(b)
Describe the process of transpiration in plants.
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(3)
(Total 6 marks)
Q10.
Some students set up the following apparatus.
The balances show the same mass at the start of the investigation.
After 24 hours the mass of flask B was the same but the mass of flask A had changed.
(i)
Describe and explain the change to the mass of flask A.
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(3)
Page 12 of 55
(ii)
Why did the students need to set up flask B?
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(1)
(Total 4 marks)
Q11.
A potted plant was left in a hot, brightly lit room for ten hours. The plant was not watered
during this period. The drawings show how the mean width of stomata changed over the ten
hour period.
(a)
Why do plants need stomata?
.....................................................................................................................................
(1)
(b)
Name the cells labelled X on the drawing.
.....................................................................................................................................
(1)
(c)
The width of the stomata changed over the ten hour period.
Explain the advantage to the plant of this change.
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(2)
(Total 4 marks)
Page 13 of 55
##
The following sentences are about the blood system. Choose words from the list in the box to
complete these sentences. You may use a word once or not at all.
diffuse
raised
lowered
narrow
one
two
wide
spread
Capillaries have thin walls which are ................................... .cell thick. This allows
nutrients from digested food to .................................... through and reach the cells
of organs. Capillaries are very ................................. .and so blood flow through an
organ is slowed down and blood pressure is ........................................ .
(Total 4 marks)
Q13.
The drawings show the structure of three types of blood vessel, A, B and C. They are
drawn to the scales indicated.
(a)
Name the three types of blood vessel.
A ..............................................................
B ..............................................................
C ..............................................................
(3)
(b)
Describe the job of blood vessel B.
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(2)
(Total 5 marks)
Page 14 of 55
Q14.
The diagram shows human blood seen through a microscope.
Write the correct letter, A, B, C or D, next to each function.
Function
Part of blood
A, B, C or D
Transports oxygen
Helps blood to clot at the site of a cut
Transports urea
(Total 3 marks)
Q15.
The diagram represents the human blood circulation system.
(a)
A, B, C and D are blood vessels.
Page 15 of 55
(i)
Give the letter of one blood vessel that is an artery.
....................................
(1)
(ii)
Give the letter of one blood vessel that is a vein.
....................................
(1)
(b)
A student pedalled an exercise cycle at constant speed for 5 minutes. The student’s heart
rate was recorded at one-minute intervals during the exercise. The results are shown in
the graph.
(i)
What was the student’s heart rate before the exercise began?
................................................ per minute
(1)
(ii)
How long was it before the student’s heart rate reached 124 beats per minute?
...................................................... .minutes
(1)
(c)
Which of the following parts of the blood carries most oxygen?
Draw a circle around one answer.
plasma
red blood cells
white blood cells
(1)
(Total 5 marks)
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Page 16 of 55
Q16.
Blood contains red blood cells, white blood cells and platelets.
(a)
Give the function of platelets.
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(1)
The photograph shows a red blood cell.
(b)
The average diameter of a real red blood cell is 0.008 millimetres.
On the photograph, the diameter of the red blood cell is 100 millimetres.
Use the formula to calculate the magnification of the photograph.
diameter on photograph = real diameter × magnification
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Magnification = ....................................
(2)
(c)
Some blood capillaries have an internal diameter of approximately 0.01 millimetres.
Use information given in part (b) to explain why only one red blood cell at a time can pass
through a capillary.
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(1)
Page 17 of 55
(d)
(i)
Red blood cells transport oxygen.
Explain how oxygen is moved from the lungs to the tissues.
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(3)
(ii)
Red blood cells have no nucleus.
Explain how this feature is an adaptation to the function of red blood cells.
...............................................................................................................
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(1)
(e)
Oxygen is exchanged between the blood capillaries and the tissue.
Give two ways in which capillaries are adapted for exchanging oxygen with the tissues.
1 .....................................................................................................................
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2 .....................................................................................................................
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(2)
(Total 10 marks)
Q17.
Ethanol (alcohol) can be mixed with petrol and used as a fuel in motor vehicles.
(a)
Which type of microorganism is used to make ethanol from sugar?
Draw a ring around one answer.
bacterium
mould
yeast
(1)
Page 18 of 55
(b)
Read the information about ethanol and petrol.
Ethanol
•
•
•
One litre releases 23.5 megajoules of energy when it is burned.
It releases carbon dioxide and water when it is burned.
It can be made from crops such as sugar cane and maize.
Petrol
•
•
•
(i)
One litre releases 34.8 megajoules of energy when it is burned.
It releases carbon dioxide, water, carbon monoxide, sulfur dioxide and oxides of
nitrogen when it is burned.
It is made from crude oil which is pumped out of the ground.
Use the information above to explain two advantages of using ethanol rather than
petrol as a fuel in motor vehicles.
Explanation 1 ....................................................................................................
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Explanation 2 ....................................................................................................
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(4)
(ii)
Give one disadvantage of using ethanol rather than petrol as a fuel in motor vehicles.
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(1)
(Total 6 marks)
Page 19 of 55
Q18.
Some students investigated the production of biogas from animal manure.
They used the apparatus shown in the diagram.
In their first investigation, the students collected the biogas in the gas syringe.
The table shows the percentage composition of the biogas.
(a)
Gas
Percentage
composition
Methane
55
Carbon dioxide
40
Water vapour
5
To make the biogas a more efficient fuel, the percentages of two of the gases in the table
should be reduced.
Which two gases should these be?
1 ............................................................
2 ............................................................
(1)
Page 20 of 55
(b)
The students then used the apparatus for a second investigation.
They bubbled oxygen through some fresh manure and water for one hour.
They then set up the apparatus again and collected a second sample of biogas in the gas
syringe.
Predict the effect of this procedure on the composition of the second sample of biogas.
Explain your answer.
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(4)
(Total 5 marks)
Q19.
A marathon runner loses a lot of sweat during a race.
(a)
Complete the following sentence.
Sweat contains water and ..............................................................................
(1)
Page 21 of 55
(b)
The table shows the concentration of glucose, ions and protein in four sports drinks,
A, B, C and D.
Runners drink sports drinks to replace the water lost in sweating. Replacing water is called
rehydration.
Scientists have shown that the ratio of the glucose concentration, in g per dm3, to the ion
concentration, in mg per dm3, in a drink affects the rate of rehydration.
The nearer this ratio is to 1:1, the faster the body rehydrates.
(i)
Drink
Glucose
in g per dm3
Ions
in mg per dm3
Protein
in g per dm3
Glucose to ion
ratio
A
110
22
1.2
5:1
B
64
96
0.0
2:3
C
72
80
0.0
......................
D
138
23
0.2
......................
Which drink, A, B, C or D, would give the runner most energy?
(1)
(ii)
Calculate the glucose to ion ratios for drinks C and D.
Write your answers in the table.
(2)
(iii)
Which drink, A, B, C or D, would rehydrate the runner the fastest?
(1)
(c)
The kidney controls the amount of water in the runner’s body.
The table shows:
•
the volume of water filtered from the blood
•
the volume of urine produced in one day.
Volume per day
in dm3
Water filtered from blood
Urine
180
2
Calculate the volume of water reabsorbed into the blood in one day.
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Volume of water that is reabsorbed ............................ dm3
(1)
Page 22 of 55
(d)
On a hot sunny afternoon:
•
man A sat in the shade, drinking beer
•
man B went jogging in the desert.
Complete the table to compare the volume and concentration of urine produced by the
kidneys of the two men.
Tick ( ) one box on each row.
Compared with Man A
The
same
Higher
Lower
the volume of urine produced by man B would be
the concentration of urine produced by man B’s
kidneys would be
(2)
(Total 8 marks)
Q20.
(a)
Which two of the following substances are found in the urine of a healthy person?
Tick ( ) two boxes.
Glucose
Mineral ions
Proteins
Water
(2)
Page 23 of 55
(b)
A person with kidney disease can be treated by dialysis.
The diagram shows how dialysis works.
The circles represent molecules of different substances.
Draw a ring around the correct word or phrase to complete each sentence.
blood cells
(i)
During dialysis, urea moves out of the
.
blood plasma
dialysis fluid
(1)
blood cells
(ii)
During dialysis, urea moves into the
blood plasma
.
dialysis fluid
(1)
diffusion
(iii)
Urea moves by the process of
digestion
.
transpiration
(1)
impermeable
(iv)
To allow the movement of urea, the dialysis membrane is
partially
permeable
.
thick
(1)
Page 24 of 55
(v)
The urea can pass through the membrane because
large
the urea molecules are
round
.
small
(1)
(c)
For most patients a kidney transplant is better than continued dialysis treatment.
Tick ( ) one box to complete the sentence.
One major problem with a kidney transplant is that
drug treatment is needed to suppress the immune system.
hospital visits are needed three times a week.
yearly costs are higher than for dialysis.
(1)
(Total 8 marks)
Q21.
The kidneys regulate the concentration of substances in the blood.
(a)
Glucose is found in the blood but not in the urine.
Describe the processes that prevent glucose being excreted in the urine.
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(3)
Page 25 of 55
(b)
The table shows the concentrations of dissolved substances in the urine of a healthy
person and the urine of a person with one type of kidney disease.
Concentration in grams per dm3
Substance
Urine of a healthy
person
Urine of a person with
kidney disease
Protein
0
6
Glucose
0
0
Amino acids
0
0
Urea
21
21
Mineral ions
19
19
(i)
Suggest an explanation for the difference in composition of the urine between the
healthy person and the person with kidney disease.
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(2)
Page 26 of 55
(ii)
In this question you will be assessed on using good English, organising information
clearly and using specialist terms where appropriate.
The person with the kidney disease could be treated either by using a dialysis
machine or by a kidney transplant operation.
Compare the advantages and disadvantages of these two methods of treatment.
Use your knowledge and understanding of the two methods in your answer.
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(6)
(Total 11 marks)
Q22.
(a)
(i)
Urine is made in the kidneys and stored for a few hours before being released
from the body.
In which organ of the body is urine stored? Draw a circle around one answer.
bladder
large intestine
liver
(1)
Page 27 of 55
(ii)
Which two of the following substances are not found in the urine of a healthy
person?
Tick ( ) two boxes.
glucose
mineral ions
protein
urea
(2)
(b)
A person with kidney disease may be treated by dialysis or by having a kidney transplant.
Read the information about dialysis and kidney transplants.
•
A person needs 3 dialysis sessions a week, each lasting about 8 hours.
•
Intake of protein and salt in the food is kept low between dialysis sessions.
•
For each patient, dialysis costs £30 000 per year.
•
The use of a general anaesthetic can sometimes cause brain damage.
•
Drugs to suppress the immune system are given after a kidney transplant.
•
A transplant costs £20 000 in the first year plus £6500 in each of the following years
for drugs.
Use this information to answer the questions.
(i)
Give two advantages of treatment by having a kidney transplant rather than treatment
by dialysis.
1 .......................................................................................................................
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2 .......................................................................................................................
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(2)
(ii)
Give one disadvantage of treatment by having a kidney transplant.
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(1)
Page 28 of 55
(c)
The table shows the amounts of some substances in the blood of one patient before
dialysis and after dialysis.
Concentration in blood plasma
in grams per dm3
Substance
Before dialysis
After dialysis
Sodium ions
2.88
3.00
Potassium ions
0.22
0.14
Urea
4.50
0.30
During dialysis, substances are removed from the blood.
(i)
Which substance in the table decreased in concentration the most during dialysis?
...........................................................................................................................
(1)
(ii)
By how much did the concentration of this substance decrease?
................................................... grams per dm3
(1)
(Total 8 marks)
Q23.
The table gives information about the growth of different types of organism.
The figures were obtained during the period of fastest growth for each organism.
Organism
(a)
(i)
Time taken to double in
mass
Bacteria
40 minutes
Yeasts
2 hours
Fusarium
4 hours
Algae
5 hours
Soybeans
1 week
Cattle
8 weeks
Which type of organism grows the fastest? ......................................................
(1)
(ii)
How many times faster than cattle do soybeans double in mass?
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(1)
Page 29 of 55
(iii)
Fusarium grows at its fastest rate in a fermenter.
Some scientists put one tonne of Fusarium into a fermenter.
Use data from the table to calculate how much Fusarium there would be in the
fermenter after 8 hours.
Draw a ring around one answer.
2 tonnes
4 tonnes
8 tonnes
(1)
(b)
Fusarium is used to make mycoprotein.
Read the information about substances found in mycoprotein.
•
•
•
Protein – can be used for making cells, enzymes and antibodies.
Fats – are rich in energy but large amounts in the diet can cause circulatory problems.
Dietary fibre – helps to reduce the risk of colon cancer.
The table compares the composition of mycoprotein and beef.
Substance
Percentage of dry mass
Mycoprotein
Beef
Protein
47.2
68.3
Fat
13.5
30.1
Dietary fibre
19.2
0.0
Use the information above to answer the questions.
(i)
Give two reasons why it would be better to eat mycoprotein instead of beef.
1 ........................................................................................................................
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2 ........................................................................................................................
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(2)
(ii)
Give one reason why it would be better to eat beef instead of mycoprotein.
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(1)
(Total 6 marks)
Page 30 of 55
Q24.
The diagram shows a fermenter. This fermenter is used for growing the fungus Fusarium
which is used to make mycoprotein.
(a)
Bubbles of air enter the fermenter at A.
Give two functions of the air bubbles.
1 .................................................................................................................................
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2 .................................................................................................................................
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(2)
(b)
Glucose is added to the fermenter at B.
Explain why glucose is added.
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(1)
Page 31 of 55
(c)
The fermenter is prevented from overheating by the cold water flowing in through the heat
exchanger coils at C.
Explain what causes the fermenter to heat up.
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(1)
(d)
It is important to prevent microorganisms other than Fusarium from growing in the
fermenter.
(i)
Why is this important?
..........................................................................................................................
..........................................................................................................................
(1)
(ii)
Suggest two ways in which contamination of the fermenter by microorganisms could
be prevented.
1 .................................................................................................................................
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2 .................................................................................................................................
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(2)
(e)
Human cells cannot make some of the amino acids which we need. We must obtain these
amino acids from our diet.
The table shows the amounts of four of these amino acids present in mycoprotein, in beef
and in wheat.
Name of
amino acid
Amount of amino acid per 100 g
in mg
Daily
amount
needed by a
70 kg human
in mg
Mycoprotein
Beef
Wheat
Lysine
910
1600
300
840
Methionine
230
500
220
910
Phenylalanine
540
760
680
980
Threonine
610
840
370
490
Page 32 of 55
A diet book states that mycoprotein is the best source of amino acids for the human diet.
Evaluate this statement.
Remember to include a conclusion in your evaluation.
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(4)
(Total 11 marks)
Page 33 of 55
Q25.
The design of biogas generators depends upon the climate.
Photograph 1 shows a biogas generator on a farm in India.
Indian biogas generator, © engINdia, http://home2.btconnect.com/engindia, 2005
(a)
Describe the processes that occur in the biogas generator.
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(3)
Page 34 of 55
(b)
The graph shows the effect of temperature on the rate of biogas production.
Temperatures in India frequently rise to 40°C and above.
The biogas generator shown in Photograph 1 is built mainly underground.
Use information from the graph to suggest why.
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(2)
Page 35 of 55
(c)
Photograph 2 shows a set of three biogas generators built at a sewage works in the UK
in 2004.
Reading biogas generators, image courtesy of Black and Veatch Ltd
The UK biogas generator has been built with concrete walls, 60 cm thick.
Use information from the graph above to suggest why.
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(2)
(Total 7 marks)
Q26.
Ethanol (alcohol) can be mixed with petrol and used as a fuel in motor vehicles.
(a)
Which type of microorganism is used to make ethanol from sugar?
Draw a ring around one answer.
bacterium
mould
yeast
(1)
Page 36 of 55
(b)
Read the information about ethanol and petrol.
Ethanol
•
•
•
One litre releases 23.5 megajoules of energy when it is burned.
It releases carbon dioxide and water when it is burned.
It can be made from crops such as sugar cane and maize.
Petrol
•
•
•
(i)
One litre releases 34.8 megajoules of energy when it is burned.
It releases carbon dioxide, water, carbon monoxide, sulfur dioxide and oxides of
nitrogen when it is burned.
It is made from crude oil which is pumped out of the ground.
Use the information above to explain two advantages of using ethanol rather than
petrol as a fuel in motor vehicles.
Explanation 1 ....................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
Explanation 2 ....................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(4)
(ii)
Give one disadvantage of using ethanol rather than petrol as a fuel in motor vehicles.
...........................................................................................................................
...........................................................................................................................
(1)
(Total 6 marks)
Page 37 of 55
M1.
D
1
A
1
C
1
[3]
M2.
(a)
No
no mark
if yes max 1 for correct statement
diffusion is down the concentration gradient
accept by diffusion ions would leave the root
1
to enter must go up / against the concentration gradient
or concentration higher in the root
or concentration lower in the soil
1
(b)
(i)
0.9 or 3.25
for correct answer with or without working
if answer incorrect 1.3 or their rate – 0.4 gains 1 mark
or 130 – 40 or 90 gains 1 mark
2
(ii)
(uptake) by active transport
1
requires energy
more energy from aerobic respiration
1
or
more energy when oxygen is present
1
[7]
Page 38 of 55
M3.
C6H12O6 + 6O2 → 6CO2 + 6H2O
(i)
energy is neutral
1
formulae all correct
with no omissions / deletions
correctly balanced
credit 1 mark if the answer is the exact
reverse of an incorrect answer for (a)
1
(ii)
and three from
take up of (soluble) substances / ions against the concentration gradient
or when the concentration (of the
substance / ions) is greater inside the
cell / cytoplasm than outside it
through the (semi-permeable) (cell) membrane energy from mitochondria
or energy from respiration
not just energy
3
[5]
M4.
(a)
B
1
(b)
C
1
(c)
D
1
(d)
(i)
upwards / outwards
1
flattened
1
(ii)
oxygen / carbon dioxide
1
[6]
M5.
(a)
(i)
increased / thick(er)
allow more / wide(r) / broad
1
(ii)
decreased
1
Page 39 of 55
(b)
1
IGNORE working or lack of working
correct figures from table 2.1 and 1.1 but no answer / wrong answer
= 1 mark
2
[4]
M6.
(a)
(i)
red cell
1
(ii)
diffusion
1
(iii)
haemoglobin
1
(iv)
a nucleus
1
(b)
(on diagram) arrow from any part of blood to air
1
[5]
M7.
(a)
any two from:
•
transport up / against concentration gradient / low to high concentration
•
uses energy
•
use of protein / carrier
2
(b)
microvilli – large(r) surface area
accept have carriers
1
mitochondria – release energy or make ATP
do not accept ‘makes energy’
1
[4]
Page 40 of 55
M8.
(a)
any two from:
•
large surface / area or many villi or have microvilli
accept big surface / area
•
thin surface or thin wall or surface 1-cell thick or
capillaries near surface or permeable or partially permeable
accept they are thin
do not allow thin cell wall
•
many blood vessels or many capillaries or capillary network
or good blood supply
ignore ‘constant blood flow’ owtte
ignore extras eg moist or reference to gases
•
have enzymes
ignore release enzymes
•
•
accept reference to lacteal as 5th point
allow reference to having mitochondria
2
(b)
(i)
small(er) (surface area) / flat(ter) / short(er)
or not as folded
or fewer capillaries owtte
allow small(er) lacteal
ignore references to wide / thick / spread out etc
1
(ii)
less absorption (of digested food) / less digestion / diffusion
accept slower for less
accept description of less digestion
accept less food can get in
do not allow zero absorption
do not allow ‘collection’ of nutrients
1
[4]
M9.
(a)
(i)
photosynthesis
1
(ii)
respiration
do not credit combustion
do not credit decay
1
(iii)
dry
accept hot or windy or drought
1
Page 41 of 55
(b)
any three from
* evaporation (of water)
or loss of water vapour
* (mostly) from the leaf / leaves
do not credit incorrect reference to leaves
* through the stomata
accept through each stoma
accept through the stomas(sic)
* causing a pull
or causing an increase in osmotic potential (at the top of the plant)
or causing an increase in water potential (at the top of the plant) or
causing a decrease in osmotic pressure (at the top of the plant)
* (so that) water moves up (through the plant)
do not credit water vapour moves up through the plant
* as the transpiration stream
* water enters through roots (and goes up plants)
3
[6]
M10.
(i)
the mass got less
accept it got lighter
award 1 mark for water was lost from the plant
1
water was taken into the plant or roots
absorbed water
do not accept soaked into plant
1
and lost through transpiration or the
leaves or evaporated from the leaves
or stomata
1
(ii)
to check the effect of the plant or to
act as a control or to show that it was
not due to evaporation from water
do not accept to keep it fair or to check that it was fair
do not accept fair test
1
[4]
Page 42 of 55
M11.
(a) allow carbon dioxide to enter / gaseous exchange (oxygen neutral)
(transpiration neutral)
for one mark
1
(b)
guard (cells)
for one mark
1
(c)
stops / reduces the rate of water loss / transpiration (reject if dark initiated)
stops / reduces wilting / description e.g. drooping / maintains turgor
for 1 mark each
2
[4]
M12.
one;
1
diffuse;
1
narrow;
1
lowered;
1
[4]
M13.
(a) A vein / venule
B capillary
C artery / arteriole
each for 1 mark
3
(b)
idea that substances or named substance pass in or out / diffuses
between blood and tissue
each for 1 mark
e.g. oxygen passes from blood to cells gains 2 marks
2
[5]
Page 43 of 55
M14.
B
1
C
1
A
1
[3]
M15.
(a)
(i)
A or C
allow lower case
1
(ii)
B or D
allow lower case
1
(b)
(i)
60
1
(ii)
4
1
(c)
red blood cells
1
[5]
M16.
(a)
forming clot at site of wound
1
(b)
12 500
correct answer gains 2 marks
if answer incorrect,
gains 1 mark
ignore any units
2
Page 44 of 55
(c)
size of RBC approximately same size as capillary
or
no room for more than one cell
or
only one can fit
or
RBC is too big
allow use of numbers
do not accept capillaries are narrow
1
(d)
(i)
in lungs oxygen diffuses (from the alveoli) into the blood
1
in the red blood cell, oxygen combines with haemoglobin,
forming oxyhaemoglobin
1
in tissues oxyhaemoglobin splits up, releasing oxygen,
which diffuses into the cells
1
(ii)
allows cell to have more haemoglobin for oxygen transport
1
(e)
thin walls for short diffusion path
1
narrow, so have a large surface area to volume ratio
1
[10]
M17.
(a)
yeast
1
(b)
(i)
two sensible suggestions, each linked to correct explanation:
(max 4 marks)
does not release CO
1
gas is toxic / harms living organisms
allow ethanol only releases CO2 and H2O for 1 mark
1
does not release NOx / SO2
do not allow more pollution / more gases released
1
gas(es) cause acid rain / eq / harms organisms
1
Page 45 of 55
or
does not cause acid rain (1)
(acid rain) damages building / harms organisms (1)
made from crops / not a fossil fuel (1)
crops can re-grow / source is renewable / fossil
fuels are non-renewable (1)
(ii)
any one from
•
releases less energy (per litre)
•
need to burn more to cover same distance / travel
shorter distance
•
land not being used for food crops / less food available
•
raises food prices
1
[6]
M18.
(a)
carbon dioxide and water vapour
either order
1
(b)
less methane
1
because less anaerobic respiration
1
more CO2
ignore water
1
because (more) aerobic respiration
1
[5]
M19.
(a)
ions
accept urea
1
Page 46 of 55
(b)
(i)
D
1
(ii)
0.9:1
accept 9:10
1
6:1
1
(iii)
C
allow ecf from (b)(ii)
1
(c)
178 dm3
1
(d)
Comp. with
Man A
The
same
Higher
Lower
urine
concentration
extra box ticked in any row cancels the mark for that row
2
[8]
M20.
(a)
mineral ions
1
water
each extra box ticked cancels 1 mark
1
(b)
(i)
blood plasma
1
(ii)
dialysis fluid
1
(iii)
diffusion
1
(iv)
partially permeable
1
(v)
small
1
Page 47 of 55
(c)
drug treatment is needed to suppress the immune system
1
[8]
M21.
(a)
glucose is filtered out of the blood
1
the filtered glucose is then taken back into the blood / reabsorbed
allow absorbed into the blood but not absorbed unqualified
1
by active transport
1
(b)
(i)
in a healthy person
protein not present because proteins are large (molecules)
or
because cannot pass through (filter)
1
in person with disease
the ‘filter’ allows protein through
1
(ii)
Marks awarded for this answer will be determined by the
Quality of Written Communication (QWC) as well as
standard of the scientific response.
No relevant content.
0 marks
There is a brief description of the two methods of treatment.
There is at least one disadvantage or advantage from
the examples given.
Level 1 (1–2 marks)
There is a scientific comparison of the two methods of
treatment, including at least one advantage and one
disadvantage but there is a lack of clarity and detail.
Level 2 (3–4 marks)
There is a clear and detailed scientific comparison of
the two methods of treatment, including at least two
advantages and two disadvantages.
Level 3 (5–6 marks)
Page 48 of 55
examples of biology points made in the response
advantages of transplant over dialysis
•
no build-up of toxins / keeps blood concentration constant
•
prevent high blood pressure
•
don’t need restricted diet / restricted fluid intake or
time wasted on dialysis
•
blood clots may result from dialysis
•
infection may result from dialysis
•
with dialysis, blood may not clot properly due to
anti-clotting drugs
•
cost issues (ie transplant cheaper)
disadvantages of transplant over dialysis
•
rejection / problem finding tissue match
•
use of immuno-suppressant drugs leading to other infections
•
dangers during operation
[11]
M22.
(a)
(i)
bladder
1
(ii)
glucose
1
protein
extras – CANCEL
1
(b)
(i)
any two from:
•
kidney functions all the time / not just 3 × 8 h sessions a week
allow direct quotation of correct points from the list
•
can eat high-protein foods / high salt foods
allow can eat anything
•
cheaper
•
waste of time
2
Page 49 of 55
(ii)
have to take (immunosuppressant) drugs / consequence of this
eg catch infections / may suffer brain damage / possible
rejection of kidney or become ill more easily
or
risk of brain damage (due to anaesthetic)
allow direct quotation of correct points from the list
1
(c)
(i)
urea
1
(ii)
4.2
1
[8]
M23.
(a)
(i)
bacteria
1
(ii)
8
1
(iii)
4 tonnes
1
(b)
(i)
mycoprotein contains less fat
1
or
less circulatory problems
mycoprotein contains (more) fibre
or
reduces colon cancer
it = mycoprotein
fat must be comparative
1
(ii)
beef contains more protein
it = beef
must be comparative
or
better for growth / making cells /
enzymes / antibodies
1
[6]
Page 50 of 55
M24.
(a)
circulation / mixing / described
1
or
temperature maintenance
supply oxygen
do not allow oxygen for anaerobic respiration
or
for aerobic conditions
or
for faster respiration
1
(b)
any one from:
•
energy supply / fuel
or use in respiration
do not allow just food / growth
ignore reference to aerobic / anaerobic
•
material for growth
or to make mycoprotein
1
(c)
(heat / energy) from respiration
allow exothermic reactions
allow description eg breakdown of glucose / catabolism
ignore metabolism
ignore aerobic / anaerobic
1
(d)
(i)
any one from:
•
compete (with Fusarium) for food / oxygen
or reduce yield of Fusarium
•
make toxic waste products
or they might cause disease / pathogenic
or harmful to people / Fusarium
do not allow harmful unqualified
1
Page 51 of 55
(ii)
any two from:
•
steam / heat treat / sterilise fermenter (before use)
not just clean
allow sterilisation unqualified for 1 mark
•
steam / heat treat / sterilise glucose / minerals / nutrients /
water (before use)
not just use pure glucose
•
filter / sterilise air intake
•
check there are no leaks
2
(e)
any three from:
•
beef is best or beef is better than mycoprotein(*)
•
mycoprotein mainly better than wheat(*)
•
more phenylalanine in wheat than in mycoprotein(*)
allow equivalent numerical statements(*)
•
but no information given on other amino acids / costs / foods
3
overall conclusion:
statement is incorrect
or
it would be the best source for vegetarians
or
for given amino acids, beef is the best source
or
three foods provide insufficient data to draw a valid conclusion
1
[11]
M25.
(a)
faeces / manure / plants
1
broken down by fermentation /anaerobic respiration
1
into methane
1
Page 52 of 55
(b)
cools digester
1
optimum temperature for process less than external temperature
1
(c)
temperatures in UK usually below optimum for process
1
heat from fermentation retained in digester to increase rate of reaction
1
[7]
M26.
(a)
yeast
1
(b)
(i)
two sensible suggestions, each linked to correct explanation:
(max 4 marks)
does not release CO
1
gas is toxic / harms living organisms
allow ethanol only releases CO2 and H2O for 1 mark
1
does not release NOx / SO2
do not allow more pollution / more gases released
1
gas(es) cause acid rain / eq / harms organisms
1
or
does not cause acid rain (1)
(acid rain) damages building / harms organisms (1)
made from crops / not a fossil fuel (1)
crops can re-grow / source is renewable / fossil
fuels are non-renewable (1)
Page 53 of 55
(ii)
any one from
•
releases less energy (per litre)
•
need to burn more to cover same distance / travel
shorter distance
•
land not being used for food crops / less food available
•
raises food prices
1
[6]
Page 54 of 55
Page 55 of 55