1 markPlant roots absorb water from soil.
This water is transported to the leaves and then moves into the air.
Which of these processes is used to absorb water from the soil?
| ☐ | A | Active transport | |
| ☐ | B | Diffusion | |
| ☐ | C | Evaporation | |
| ☐ | D | Osmosis |
1 markName the tissue that transports water to the leaves.
2 marksGive two uses of water in a plant.
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4 marksBlood consists of cells and plasma.
Plasma transports various substances to and from different parts of the body.
Describe the function of plasma in transporting named substances in the body.
5 marksThe diagram shows a white blood cell called a phagocyte.
The magnification of the cell is calculated using this formula.
The actual diameter of the cell is 0.013 mm.
Calculate the magnification of the cell. A ruler has been added to the diagram to help your calculations.
(2)
Name the structure labelled A in the diagram.
(1)
Describe the function of this cell in defending the body from infection.
(2)
1 markOther white blood cells produce proteins called antibodies.
State how you could test a sample of plasma for protein.
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2 marksThe diagram shows a cross‐section through a leaf.
Which layer contains palisade mesophyll cells?
(1)
| ☐ | A | Layer A | |
| ☐ | B | Layer B | |
| ☐ | C | Layer C | |
| ☐ | D | Layer D |
Which set of environmental conditions would produce the fastest rate of transpiration from this leaf?
(1)
| Humidity | Temperature | ||
| ☐ | A | High | High |
| ☐ | B | High | Low |
| ☐ | C | Low | High |
| ☐ | D | Low | Low |
10 marksScientists investigate the effect of changing carbon dioxide concentration on the density of stomata of wheat plants.
They grow wheat plants from seed in different concentrations of carbon dioxide.
After three weeks, they take a leaf from each plant and calculate the mean density of stomata.
State the independent variable in this investigation.
(1)
Give two abiotic variables that the scientists could control.
(2)
To calculate the mean density of stomata, leaf sections are viewed with a microscope.
The number of stomata within six circular areas of the leaf are counted.
The results for one leaf are shown in the table.
| Leaf area number | Per number of stomata |
| 1 | 68 |
| 2 | 72 |
| 3 | 66 |
| 4 | 75 |
| 5 | 76 |
| 6 | 63 |
The radius of each circular area is 0.40 mm.
area of circle = πr2
[π = 3.14]
Calculate the mean density of stomata on the leaf surface. Give your answer in stomata per mm2.
(3)
The investigation shows that in increased carbon dioxide concentrations there is a lower mean density of stomata.
The scientist concludes that in hot dry areas, with increased carbon dioxide concentrations, it would be an advantage for wheat to have a lower mean density of stomata.
Discuss the scientist’s conclusion.
(4)
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6 marksThe diagram shows the path that the water takes when it is absorbed from the soil into the xylem of a plant.
Explain how root hair cells are adapted for efficient absorption of water.
(2)
Explain how water is transported from the soil to the leaves.
(4)
4 marksDescribe how you could determine the rate of water loss from a leafy shoot.
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4 marksThe diagram shows a magnified image of a root hair cell from a young plant.
Give the names of structures labelled W, X, Y and Z.
2 marksThe actual length of the cell, along the line between A and B, is 1000 μm.
Calculate the magnification of this drawing.
6 marksExplain the role of the root hair cell in absorption of water from the soil.
(3)
Sometimes gardeners give their plants too much water. The water fills up the air spaces in the soil around the plant roots. Explain how this can lead to plants failing to grow properly.
(3)
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2 marksP. multocida is a bacterium that causes cholera in chickens.
The diagram shows the bacterium.
Give two structures in this bacterium that are also found in all eukaryotic cells.
5 marksScientists investigated the survival of chickens injected with normal P. multocida or with weakened P. multocida.
The table shows the scientists’ results.
| Type of injection | Result |
| normal P. multocida | chickens die |
| weakened P. multocida | chickens stay alive |
What is a correct conclusion about P. multocida from these results?
(1)
| ☐ | A | They are decomposers | |
| ☐ | B | They are pathogens | |
| ☐ | C | They are microscopic | |
| ☐ | D | They are non-living |
The scientists took the living chickens that had been injected with weakened P. multocida and then injected them with normal P. multocida.
The chickens did not die, as they were now immune.
Explain why these chickens did not die.
(4)
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2 marksThe diagram shows the human heart with four blood vessels labelled A, B, C and D.
Which blood vessel brings oxygenated blood to the heart?
(1)
| ☐ | A | ||
| ☐ | B | ||
| ☐ | C | ||
| ☐ | D |
Which blood vessel contains blood at the highest pressure?
(1)
| ☐ | A | ||
| ☐ | B | ||
| ☐ | C | ||
| ☐ | D |
3 marks(1)
Describe the function of the semi-lunar valves.
(2)
5 marksIn the heart of a foetus, the two upper chambers (atria) are linked by a hole so that blood can pass between them.
Explain why this hole is normally closed before the baby is born.
(2)
Sometimes the hole does not close.
Explain what effect this will have on the baby.
(3)
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4 marksSickle cell anaemia is a condition in which some of the person’s red blood cells develop abnormally.
The diagram shows red blood cells from a healthy person and red blood cells from a person with sickle cell anaemia.
A person with sickle cell anaemia often suffers pain as some of their blood vessels become blocked by the sickle cells.
Suggest why the person’s blood vessels may become blocked.
(1)
People with sickle cell anaemia have symptoms of tiredness and joint pain that get worse if they are exposed to cold temperatures and high altitudes.
Suggest why these symptoms get worse.
(3)
3 marksSickle cell anaemia is caused by a single recessive allele.
State what is meant by the term recessive.
(1)
A man and a woman who are both heterozygous for the sickle cell allele have a child.
Calculate the probability that the child will be female and not have sickle cell anaemia.
(2)
1 markSickle cell anaemia is more common in countries where malaria is found. This is because having an allele for sickle cell anaemia can reduce the likelihood of developing malaria.
Which type of organism causes malaria?
| ☐ | A | Bacterium | |
| ☐ | B | Fungus | |
| ☐ | C | Plant | |
| ☐ | D | Protoctist |
1 markWhat is the name of the pigment found in red blood cells?
| ☐ | A | chlorophyll | |
| ☐ | B | haemoglobin | |
| ☐ | C | iron | |
| ☐ | D | magnesium |
2 marksGive two differences in structure between red blood cells and white blood cells.
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1 markRead the passage below. Use the information in the passage and your own knowledge to answer the questions that follow.
Suggest why cardiomyopathy can cause heart failure (lines 6 to 7).
3 marksDuring the transplant procedure the patient’s heart is removed, leaving behind a section of the right and left atria.
Describe the functions of the atria in the body.
2 marksDescribe how the blood in the pulmonary artery differs from the blood in the aorta.
3 marksExplain the function of the heart-lung bypass machine (lines 11 to 12).
2 marksExplain why the patient needs to be given immunosuppressants (lines 19 to 20).
2 marksExplain why patients should not smoke after their heart transplant (lines 28 to 29).
1 markState what is meant by the term balanced diet.
2 marksCalculate the number of patients in the United Kingdom who have a heart transplant in one year that are still alive five years later (lines 2 to 3 and lines 35 to 36).
1 markSuggest why patients are advised to avoid strenuous activities after their heart transplant (line 24).
1 markSuggest why patients are more likely to be at risk of food poisoning after their heart transplant (lines 32 to 33).
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2 marksAerobic respiration uses oxygen and produces ATP.
Complete the word equation for aerobic respiration.
oxygen + .......................... → .......................... + .......................... + ATP
3 marksA scientist investigates the rates of aerobic respiration of some animals.
The scientist calculates the rate of respiration per gram of each animal.
The results are shown in the table.
| Animal | Rate of aerobic respiration per gram of animal in arbitrary units |
| Frog | 150 |
| Human | 200 |
| Mouse | 1500 |
Explain why a mouse uses more oxygen per gram than a human.
7 marksThe structure of a frog heart is different from the structure of a human heart.
The diagram shows a section of a frog heart with arrows showing the direction of blood flow.
What is the name of the blood vessel labelled X?
(1)
| ☐ | A | aorta | |
| ☐ | B | pulmonary artery | |
| ☐ | C | pulmonary vein | |
| ☐ | D | vena cava |
Give one difference between the structure of the frog heart and a human heart.
(1)
Humans can run for long periods of time. Frogs can only move for short periods of time.
Explain how the structure of the heart of a frog means that it is unable to move for long periods of time.
(5)
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2 marksHuman blood contains red blood cells and white blood cells.
The table shows the number of these blood cells in a sample of blood.
| Type of cell | Number of cells per mm3 | Number of cells per mm3 in standard form |
| Red blood cell | 5 000 000 | 5.0 × 106 |
| White blood cell | 6000 |
Complete the table to give the number of white blood cells per mm3 in standard form.
(1)
What is the number of red blood cells in 1000 cm3 of this person's blood?
(1)
| ☐ | A | 5.0 × 106 | |
| ☐ | B | 5.0 × 109 | |
| ☐ | C | 5.0 × 1011 | |
| ☐ | D | 5.0 × 1012 |
4 marksThe table gives names, descriptions and symptoms of two blood conditions.
| Name of condition | Description | Symptom |
| Anaemia | Low red blood cell count | Often tired |
| Leukopenia | Low white blood cell count | Likely to get infections |
Explain why a person with anaemia is often tired.
(2)
Explain why a person with leukopenia is more likely to get an infection.
(2)
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1 markCholesterol is needed in the diet for making cell membranes.
State the role of the cell membrane.
2 marksToo much cholesterol is a health risk because fatty deposits build up in arteries.
The lumen of an artery had a diameter of 4.0 mm before the build-up of a fatty deposit.
The fatty deposit covers 45 % of the original area of the lumen.
Calculate the area in mm2 of the lumen that is available for blood flow.
[area of the lumen = πr2]
[π = 3.14]
8 marksA scientist tests the blood cholesterol concentration in a sample of men between 25 and 34 years old.
The scientist groups the men in ranges of blood cholesterol concentration and counts the number of men in each range.
The table gives the scientist’s results.
| Range of blood cholesterol concentration in mg per cm3 | Number of men in each range |
| 80 to 119 | 13 |
| 120 to 159 | 150 |
| 160 to 199 | 442 |
| 200 to 239 | 299 |
| 240 to 279 | 115 |
| 280 to 319 | 34 |
| 320 to 359 | 9 |
| 360 to 399 | 5 |
Plot a suitable graph on the grid to show these results.
(5)
Which range of blood cholesterol levels is the mode for this sample?
(1)
| ☐ | A | 80 to 119 | |
| ☐ | B | 80 to 379 | |
| ☐ | C | 160 to 199 | |
| ☐ | D | 360 to 399 |
A blood cholesterol level greater than 239 mg per 100 cm3 means a person has a higher risk of heart disease.
Calculate the percentage of men in the sample at a higher risk of heart disease.
(2)
4 marksStatins are drugs that reduce blood cholesterol levels.
A scientist investigates the use of one type of statin on the risk of having a heart attack.
He gives the statin to one group of people and gives a control substance to another group of people.
He calculates the percentage of people in each group that has a heart attack during the next four years.
The table gives the scientist’s results.
| Group | Percentage (%) having heart attacks |
| Statin | 2.2 |
| Control substance | 3.8 |
A conclusion from this data is that statins reduce the risk of heart attacks.
Discuss this conclusion.
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7 marksThe diagram shows the human circulation system with some blood vessels labelled A to J. The arrows show the direction of blood flow.
The table gives some statements about the content of blood vessels in this circulation system.
Complete the table by giving the letter of the blood vessel that matches each statement.
(5)
| Statement | Letter |
| Contains the least carbon dioxide | |
| Contains the most glucose after a meal | |
| Contains the least oxygen | |
| Contains the least urea | |
| Contains blood at the highest pressure |
State two ways in which the structure of blood vessel A differs from the structure of blood vessel J.
(2)
5 marksMuscles in the legs contain capillaries.
A scientist investigates how long-term training affects the number of capillaries in an athlete’s leg muscles.
The scientist determines the mean number of capillaries per mm2 in samples of leg muscle from the athlete before and after a period of training.
The table shows the scientist’s results.
| Muscle sample | Mean number of capillaries per mm2 |
| Before training | 313 |
| After training | 349 |
The scientist concludes that training improves the athletic performance.
Discuss this conclusion.
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1 markRead the passage below. Use the information in the passage and your own knowledge to answer the questions that follow.
César Astudillo from Collado Villalba, Spain, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons. Image cropped and colour removed.
| Blood group | Antigens present |
| A | A |
| B | B |
| AB | A and B |
| O | Neither A nor B |
Name the type of cell that produces antibodies. (Lines 8 and 9)
2 marksCalculate the number of blood donations collected per year from the high‐income countries. (Lines 14 and 15)
Give your answer in standard form.
3 marksSome scientists have suggested that spherical artificial red blood cells transport oxygen less efficiently than normal human red blood cells.
Explain why the shape of the artificial red blood cells reduces the efficiency of oxygen transport compared to normal human red blood cells. (Lines 18 and 19)
2 marksExplain why the artificial red blood cells are suspended in sodium chloride solution instead of in water. (Line 20)
4 marksExplain why stem cells can be used to make large quantities of red blood cells. (Lines 22 and 23)
(2)
Suggest why the scientists made red blood cells with blood group O. (Lines 22 and 23)
(2)
2 marksGive two substances found in blood plasma that are not present in the artificial blood. (Lines 28 and 29)
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