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1

Some features of cells are listed. cell wall cell surface membrane ribosomes Which features can be found in plant cells and in prokaryotic cells?

1. Cell structure  →  1.2. Cells as the basic units of living organisms

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2

Which of these statements about light microscopy are correct?

1. Cell structure  →  1.1. The microscope in cell studies

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3

Which type of cell contains the highest proportion of cell structures bound by a single membrane?

1. Cell structure  →  1.2. Cells as the basic units of living organisms

4. Cell membranes and transport  →  4.1. Fluid mosaic membranes

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4

The table shows a variety of structures which may be found in cells. Which row shows structures that could be found in the root cells of a plant?

1. Cell structure  →  1.2. Cells as the basic units of living organisms

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5

Which of these cell structures are present in Plasmodium?

1. Cell structure  →  1.2. Cells as the basic units of living organisms

6. Nucleic acids and protein synthesis  →  6.1. Structure of nucleic acids and replication of DNA

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6

A student was asked to estimate the concentration of glucose in a solution using the Benedict’s test. The student was provided with a 1.0 mol dm–3 glucose solution and was told to make a 0.6 mol dm–3 solution by proportional dilution. Which row shows the correct volumes of both 1.0 mol dm–3 glucose solution and distilled water needed to make the 0.6 mol dm–3 solution?

2. Biological molecules  →  2.1. Testing for biological molecules

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7

The diagram shows part of a carbohydrate molecule formed by glucose. What is the name of the molecule?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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8

The diagram shows the relationship between some biological molecules. Which row is correct?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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9

Which diagram shows the reaction that occurs to join two of the monomers that form cellulose?

2. Biological molecules  →  2.2. Carbohydrates and lipids

12. Energy and respiration  →  12.2. Respiration

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10

Which molecules contain C=O bonds?

2. Biological molecules  →  2.2. Carbohydrates and lipids

2. Biological molecules  →  2.3. Proteins

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11

Which row describes a collagen molecule?

2. Biological molecules  →  2.3. Proteins

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12

A student investigated the hydrolysis of the lipid in high-fat milk, using the enzyme lipase. • 1 cm3 of enzyme solution was added to 10 cm3 of high-fat milk. • The temperature was kept constant. • The pH of the reaction mixture was recorded at time 0 minutes and every minute for 20 minutes. Which statements could be supported by the results of the investigation?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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13

A student carried out an investigation into the effect of temperature on the rate of an enzyme-catalysed reaction. At each temperature, the substrate concentration was measured after 10 minutes. All the other variables were kept constant. Which graph shows the effect of increasing temperature on the substrate concentration after 10 minutes?

3. Enzymes  →  3.2. Factors that affect enzyme action

13. Photosynthesis  →  13.2. Investigation of limiting factors

12. Energy and respiration  →  12.2. Respiration

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14

The graph shows how the rate of an enzyme-catalysed reaction depends on the concentration of substrate. 0.4 0.3 0.2 0.1 0.0 initial rate of reaction / mmol s–1 substrate concentration / mmol dm–3 0.0 1.0 2.0 3.0 4.0 5.0 What is the Michaelis-Menten constant (Km) for this enzyme under these conditions?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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15

The formula shows how the rate of diffusion across a cell surface membrane can be calculated. membrane of thickness ion concentrat in difference area surface × Which row shows how the fastest rate of diffusion can be achieved?

4. Cell membranes and transport  →  4.2. Movement into and out of cells

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16

The diagram shows part of the cell surface membrane of an active animal cell. L M more negative water potential X less negative water potential Y Which statements correctly describe the net movement of molecules across this membrane?

4. Cell membranes and transport  →  4.2. Movement into and out of cells

7. Transport in plants  →  7.2. Transport mechanisms

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17

Some epidermal cells from a well-watered plant are placed in three solutions which have different water potentials. Which row correctly shows the state of the plant cells in each of the solutions?

4. Cell membranes and transport  →  4.2. Movement into and out of cells

1. Cell structure  →  1.2. Cells as the basic units of living organisms

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18

One of the chromosomes in a nucleus has a telomere which contains many repeats of the base sequence TTAGGG. This chromosome was extracted from four different cells and the total number of bases in the telomere was determined. Which total number of bases was found in the cell that had undergone the most mitotic divisions?

5. The mitotic cell cycle  →  5.1. Replication and division of nuclei and cells

5. The mitotic cell cycle  →  5.2. Chromosome behaviour in mitosis

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19

The chromosome content of each daughter cell must be identical to that of the mother cell for successful cell replacement when repairing tissues. Which stages of mitosis make sure that each daughter cell receives one chromatid from each chromatid pair?

5. The mitotic cell cycle  →  5.1. Replication and division of nuclei and cells

5. The mitotic cell cycle  →  5.2. Chromosome behaviour in mitosis

16. Inheritance  →  16.1. Passage of information from parents to offspring

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20

Which of these statements about cytokinesis is always true?

5. The mitotic cell cycle  →  5.1. Replication and division of nuclei and cells

1. Cell structure  →  1.2. Cells as the basic units of living organisms

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21

Which statement is correct about the number of telomeres present in prophase of a human body cell?

5. The mitotic cell cycle  →  5.1. Replication and division of nuclei and cells

5. The mitotic cell cycle  →  5.2. Chromosome behaviour in mitosis

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22

Which statement explains why DNA replication is described as semi-conservative?

6. Nucleic acids and protein synthesis  →  6.1. Structure of nucleic acids and replication of DNA

6. Nucleic acids and protein synthesis  →  6.2. Protein synthesis

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23

A section of a DNA molecule has the coding sequence: AGGCAATGGC. Which statements are correct?

6. Nucleic acids and protein synthesis  →  6.1. Structure of nucleic acids and replication of DNA

6. Nucleic acids and protein synthesis  →  6.2. Protein synthesis

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24

XNA is a laboratory-made nucleic acid made of nucleotides in which one component has been replaced by chemical X. The chemical X is not found in nature. The part of the molecule responsible for coding is not changed. Which organic component of a DNA or RNA nucleotide has been replaced by X?

6. Nucleic acids and protein synthesis  →  6.1. Structure of nucleic acids and replication of DNA

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25

Which statements about tRNA are correct?

6. Nucleic acids and protein synthesis  →  6.2. Protein synthesis

6. Nucleic acids and protein synthesis  →  6.1. Structure of nucleic acids and replication of DNA

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26

What is the role of ATP in a companion cell when sucrose is loaded into a sieve tube element?

7. Transport in plants  →  7.2. Transport mechanisms

7. Transport in plants  →  7.1. Structure of transport tissues

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27

A potometer was used to measure the transpiration rate of a leafy shoot. What could be the correct units?

7. Transport in plants  →  7.2. Transport mechanisms

13. Photosynthesis  →  13.2. Investigation of limiting factors

12. Energy and respiration  →  12.2. Respiration

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28

Which combination of features is characteristic of a phloem sieve tube element as it is loaded from a source?

7. Transport in plants  →  7.2. Transport mechanisms

7. Transport in plants  →  7.1. Structure of transport tissues

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29

The diagrams show transverse sections of parts of a plant. Which structures, labelled 1 to 4, transport water and sucrose?

7. Transport in plants  →  7.2. Transport mechanisms

7. Transport in plants  →  7.1. Structure of transport tissues

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30

Which statement explains why the ventricles contract after the atria?

8. Transport in mammals  →  8.3. The heart

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31

If the left atrioventricular valve in the heart does not close completely it results in blood flowing back into the atrium during ventricular systole. What would be the immediate effect of this back flow?

8. Transport in mammals  →  8.3. The heart

8. Transport in mammals  →  8.1. The circulatory system

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32

The graph shows two oxygen dissociation curves, one for a tissue at rest and one for the same tissue during exercise. pO2 / kPa percentage saturation with oxygen tissue at rest tissue during exercise What factors have caused the difference in the position of the dissociation curve during exercise compared with the dissociation curve for the tissue at rest?

8. Transport in mammals  →  8.2. Transport of oxygen and carbon dioxide

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33

Which of these statements about the formation of haemoglobinic acid are correct?

8. Transport in mammals  →  8.2. Transport of oxygen and carbon dioxide

2. Biological molecules  →  2.3. Proteins

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34

Which of these structures contain cartilage and cilia?

9. Gas exchange  →  9.1. The gas exchange system

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35

What correctly describes the effect of carcinogens on lung tissue that causes a tumour to develop?

5. The mitotic cell cycle  →  5.1. Replication and division of nuclei and cells

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36

Which row identifies both the type of pathogen that causes cholera and the way in which cholera is transmitted from person to person?

10. Infectious diseases  →  10.1. Infectious diseases

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37

Why do people with HIV/AIDS have a higher occurrence of malaria than people without HIV/AIDS?

10. Infectious diseases  →  10.1. Infectious diseases

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38

How many variable regions are there on a typical Y-shaped antibody molecule?

2. Biological molecules  →  2.3. Proteins

11. Immunity  →  11.2. Antibodies and vaccination

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39

Where are antigens found?

11. Immunity  →  11.1. The immune system

11. Immunity  →  11.2. Antibodies and vaccination

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40

When an organ is transplanted from one person to another, rejection of the non-self organ must be avoided. At the same time, the immune system of the recipient must be maintained to prevent death from infections. What prevents rejection of the transplanted organ?

11. Immunity  →  11.1. The immune system

11. Immunity  →  11.2. Antibodies and vaccination

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