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1

What are the appropriate units for measuring diameters of alveoli, diameters of white blood cells and the width of cell walls?

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

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

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2

The diagram shows a high-power drawing of a bacterium. capsule cell wall cell membrane ribosome DNA Which three components are found in both this bacterium and an animal cell?

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

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3

The diagram shows a stage micrometer scale on which the small divisions are 0.1 mm. It is viewed through an eyepiece containing a graticule. The stage micrometer scale is replaced by a slide of a plant cell. What is the width of a chloroplast?

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

13. Photosynthesis  →  13.1. Photosynthesis as an energy transfer process

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4

Which structures are found in typical eukaryotic cells?

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

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5

What is the function of the nucleolus?

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

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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6

The electronmicrograph shows a cell. ×5700 What is the actual diameter of the nucleus?

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

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

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7

A student carried out four tests for biological molecules on a solution. The observations are shown...

2. Biological molecules  →  2.1. Testing for biological molecules

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8

The diagrams show different types of bond found in biological molecules. C O N H NH O S S CH2 CH2 O C C C O C C CH2 CH2 NH2 + O– C C O O Which combination of bonds could not be found in a protein with a tertiary structure?

2. Biological molecules  →  2.3. Proteins

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9

Which row shows the correct match between the descriptions of biological molecules and where they are found?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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

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10

Which is the correct description for the structure of amylose and cellulose?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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11

Which description is correct?

2. Biological molecules  →  2.3. Proteins

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12

Polar molecules form hydrogen bonds with each other. Which properties of water result from its molecules being polar?

2. Biological molecules  →  2.4. Water

2. Biological molecules  →  2.2. Carbohydrates and lipids

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13

Which statements about the effect of all enzyme inhibitors are correct?

3. Enzymes  →  3.2. Factors that affect enzyme action

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14

The graphs show the rate of reaction of an enzyme-catalysed reaction. Which graph shows the effect of increasing the concentration of the substrate at two different concentrations of a competitive inhibitor?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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15

Which type of cell has a large number of glycoproteins on the cell surface membrane?

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

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

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16

The diagram shows the transport of ions across the cell surface membrane. Inside the cell there is a low concentration of sodium ions (Na+) and a high concentration of potassium ions (K+). Outside the cell there is a low concentration of K+ and a high concentration of Na+. The carrier molecule is a pump which exchanges Na+ for K+. cell surface membrane inside cell outside cell carrier molecule Which ionic movements are represented by the arrows?

7. Transport in plants  →  7.2. Transport mechanisms

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

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17

Which set of factors will produce the most fluid cell surface membrane?

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

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18

The graphs show various measurements taken from metaphase of mitosis onwards. The graphs are to scale when compared to one another. distance time distance time distance time X Y Z Which row correctly identifies each graph?

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

A scientist counted 22 chromosomes in each of the root cells of a xerophytic plant. What is the diploid and haploid number of chromosomes for this species?

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

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

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20

Which row shows two pairs of nucleotides formed during transcription?

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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21

Which row correctly identifies the features of DNA and RNA molecules?

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

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22

Two polynucleotide strands make up a DNA molecule. What is a correct description?

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

The diagram shows transverse sections of two plant structures. Which row shows the correct labels?

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

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24

A tissue composed of plasmolysed plant cells was put into distilled water. The graph shows how the mean cell volume changes with time. X mean cell volume time What is the cause of the plateau at X?

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

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25

The diagram shows a vascular bundle from the stem of a plant. Which row describes the functions of the labelled cells?

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

14. Homeostasis  →  14.2. Homeostasis in plants

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

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26

Which changes to the water potential and the volume of liquid in the phloem occur when amino acids are moved into a sink from phloem sieve tubes?

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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27

The graph shows the oxygen dissociation curves for haemoglobin from three different animals. partial pressure of oxygen / kPa percentage saturation of haemoglobin with oxygen X Y Z Which of the haemoglobins, X, Y or Z, would be present in each of the animals 1, 2 or 3?

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

2. Biological molecules  →  2.3. Proteins

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28

What explains how the uptake of oxygen is maximised as blood passes through the capillaries of the lungs?

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

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29

What happens after carbonic anhydrase has catalysed a reaction involved in the transport of carbon dioxide?

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

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30

The diagram shows a section through the heart and the associated blood vessels. What is correct for the flow of blood through the heart?

8. Transport in mammals  →  8.3. The heart

8. Transport in mammals  →  8.1. The circulatory system

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31

Which row shows a function of each of the named tissues in the gas exchange system?

9. Gas exchange  →  9.1. The gas exchange system

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32

The graph shows the results of a study to determine whether there is a link between the number of cigarettes smoked by a mother and the birth weight of her baby. number of cigarettes smoked by mother each day birth weight of babies / kg Which conclusions can be drawn from this graph?

16. Inheritance  →  16.2. The roles of genes in determining the phenotype

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33

What is a feature of coronary bypass surgery?

8. Transport in mammals  →  8.1. The circulatory system

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34

The first column in the table contains statements about disease. Columns headed 1-4 represent four different named diseases. statements infectious disease    can be treated with antibiotics   key caused by a virus   = true degeneration of lung tissue   What is the correct set of column headings for the table above?

10. Infectious diseases  →  10.1. Infectious diseases

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35

Which row is correct for malaria?

10. Infectious diseases  →  10.1. Infectious diseases

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36

During an outbreak of a very infectious disease, vulnerable people need immediate protection. Which type of immunity would be given to these people?

11. Immunity  →  11.2. Antibodies and vaccination

10. Infectious diseases  →  10.1. Infectious diseases

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37

Which cells become memory cells in the immune response?

11. Immunity  →  11.1. The immune system

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38

Which soil would have the smallest number of denitrifying bacteria?

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39

In an ecosystem, at which stage is most energy lost?

13. Photosynthesis  →  13.1. Photosynthesis as an energy transfer process

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40

Two species of animal are found in the same area of forest and grassland. In the spring and summer they eat the same plant food. However, in the autumn and winter one eats nuts in the forest and the other eats roots on the grassland. Both species are preyed upon by the same predator. Numbers of root-eating animals are reduced most by this, but they recover faster since they reproduce faster. What can be concluded about these two species of animals?

18. Classification, biodiversity and conservation  →  18.2. Biodiversity

18. Classification, biodiversity and conservation  →  18.1. Classification

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