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1

The diagram shows a section through a type of epithelium. 80 µm Where is this type of epithelium found in the respiratory system?

9. Gas exchange  →  9.1. The gas exchange system

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2

Which statement is an example of epidemiological evidence linking smoking to lung cancer?

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3

Which feature of haemoglobin makes it a globular protein?

2. Biological molecules  →  2.3. Proteins

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4

Which processes allow movement into and out of a cell?

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

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5

Some plant and animal cells were placed in different solutions and the results are shown...

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

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

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6

The diagrams represent the cross section of the stem, root and leaf of a non-woody dicotyledonous plant. In each section the distribution of the tissues is shown...

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

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7

What occurs in the sieve tube elements of a photosynthesising leaf and an actively growing root?

7. Transport in plants  →  7.2. Transport mechanisms

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

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8

Some soil-borne fungi cause wilting in crop plants by growing within the xylem vessels. Which process will be directly affected by these fungi?

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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9

The diagram shows part of the nitrogen cycle. nitrogen gas ammonium ions (NH4) + ammonium ions (NH4) + nitrate ions (NO3) – proteins reduction reduction Which sequence of numbers correctly shows the roles of different types of microorganism in the nitrogen cycle?

12. Energy and respiration  →  12.2. Respiration

18. Classification, biodiversity and conservation  →  18.1. Classification

11. Immunity  →  11.1. The immune system

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10

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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11

The diagram shows a tropical ocean food chain with 10 % efficiency of energy transfer between trophic levels. phytoplankton herbivorous zooplankton carnivorous zooplankton small fish tuna Net primary production of phytoplankton is 1300 g m–3 yr –1. What is the net primary production per year for the carnivorous zooplankton and the tuna?

13. Photosynthesis  →  13.2. Investigation of limiting factors

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

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12

The diagram below is drawn from an electron micrograph of an animal cell. Which represents the same cell, seen under a light microscope at ×400 magnification?

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

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13

The diagram shows a stage micrometer, with divisions 0.1 mm apart, viewed through an eyepiece containing a graticule. 0 10 20 30 40 50 60 70 80 90 10 What is the area of the field of view of the microscope at this magnification?

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

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14

Which observations suggest that a cell is eukaryotic?

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

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15

Which structures are found in both animal and plant cells?

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

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16

Which structures are measured using these units?

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

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

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17

When making measurements in experiments, which methods have parallax errors?

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

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18

Membranes within and at the surface of cells have different roles. The diagram allows the identification of the various organelles within the cell, by describing the membrane structure and function. membrane encloses cell contents cell surface membrane encloses a structure within the cell no pores present possesses pores single membrane transports enzymes lipid synthesis allows oxygen to enter allows carbon dioxide to enter double membrane protein synthesis allows exit of mRNA Which of the outcomes shown...

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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19

The diagram shows chromosomes at metaphase of mitosis. What are the diploid and haploid numbers 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

DNA is said to replicate in a semi-conservative way. Results of Meselson and Stahl’s experiments gave overwhelming support to this theory. They used E. coli which has a generation time of 50 minutes. Here are the steps in their experiment but they are in the wrong order. P All bacteria contain 15N DNA. Q All bacteria contain hybrid DNA (15N DNA and 14N DNA). R Bacteria contain either all 14N DNA or hybrid DNA. S Bacteria grown in a 15N medium for many generations. T Bacteria transferred to a 14N medium and sampled every 50 minutes. Which sequence of letters shows the correct order of the steps in the experiment?

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

19. Genetic technology  →  19.1. Principles of genetic technology

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21

What occurs in anaphase of mitosis?

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

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

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22

In a DNA molecule, the base sequence AGT codes for the amino acid serine. What is the base sequence of the anti-codon on the tRNA to which serine becomes attached?

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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23

What is the minimum number of base substitutions required to change the nucleotide sequence of the HbA allele to the HbS (sickle cell) allele?

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

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24

An enzyme is completely denatured at 50 °C. A fixed concentration of this enzyme is added to a fixed concentration of its substrate. The time taken for completion of the reaction is measured at different temperatures. Which graph shows the results?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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25

The enzyme lysozyme secreted from tear glands forms deposits on contact lenses. Which ingredient would be effective in a contact lens cleaner for removing these deposits?

3. Enzymes  →  3.2. Factors that affect enzyme action

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26

A student tested four samples of food, A, B, C and D, for the presence of • lipids • protein • reducing sugars • starch One of the food samples, milk, was found to contain lipid, protein and reducing sugar. Which of the food samples, shown...

2. Biological molecules  →  2.1. Testing for biological molecules

2. Biological molecules  →  2.2. Carbohydrates and lipids

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27

Which diagram represents part of the ring form of a molecule of β-glucose?

2. Biological molecules  →  2.2. Carbohydrates and lipids

2. Biological molecules  →  2.3. Proteins

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28

Which statement describes how the molecular structure of starch is suited to its function?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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29

Which feature distinguishes starch from glycogen?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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30

How many fatty acid residues are normally present in a phospholipid molecule?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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31

As a frozen lake warms after a cold winter, mineral nutrients are brought to the surface. Which properties of water contribute to this process?

2. Biological molecules  →  2.4. Water

8. Transport in mammals  →  8.1. The circulatory system

2. Biological molecules  →  2.2. Carbohydrates and lipids

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32

What would be the result of analysing part of a DNA molecule?

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

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33

What are the causative agents of cholera, malaria and TB?

10. Infectious diseases  →  10.1. Infectious diseases

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34

What is a difference between T-lymphocytes and B-lymphocytes in the immune system?

11. Immunity  →  11.1. The immune system

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35

In an investigation into the immune response, a volunteer was exposed to two different antigens, X and Y. The relative antibody concentration in the blood was measured at regular intervals over 60 days. The graph shows the time when the volunteer was exposed to each antigen and the antibody concentration against time for antigens X and Y. first exposure to antigen X second exposure to antigen X first exposure to antigen Y time / days antibody concentration / arbitrary units antibody for antigen X antibody for antigen Y What is the explanation for the results displayed on the graph?

11. Immunity  →  11.1. The immune system

11. Immunity  →  11.2. Antibodies and vaccination

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36

40 % of the world’s population live in an area where malaria is a threat to health. In recent years there have been many more cases in Africa. What is the social factor that is letting the spread of malaria get out of control?

10. Infectious diseases  →  10.1. Infectious diseases

11. Immunity  →  11.2. Antibodies and vaccination

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37

What is systolic blood pressure?

8. Transport in mammals  →  8.3. The heart

8. Transport in mammals  →  8.1. The circulatory system

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38

Aortic stenosis is a heart valve disorder in which the aortic semi-lunar valve opening is narrow. Which effect could aortic stenosis have on the heart structure and function?

8. Transport in mammals  →  8.3. The heart

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39

The trace represents the electrical activity of the heart during a single heart beat. P Q R S T Which letters identify the flow of current through the atria and the recovery of the ventricle walls?

8. Transport in mammals  →  8.3. The heart

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40

The diagram shows a spirometer trace with tidal volume and vital capacity. tidal volume volume / dm3 vital capacity X Y time What happens to the volumes labelled X and Y during moderate exercise?

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

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

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