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1

What is the definition of the resolution of a light microscope?

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

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2

The electron micrograph shows a type of virus at a magnification of ×30 000. What is the length of the virus?

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

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3

Which row correctly shows a feature of a cell structure?

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

2. Biological molecules  →  2.3. Proteins

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4

Four students were asked to match the function with the appearance of some cell structures in an animal cell. The functions were listed by a number. organises microtubules to produce the spindle during cell division synthesis of polypeptides packaging of hydrolytic enzymes that will remain in the cell The appearances were listed by a letter. V membranes which surround an enclosed inner cavity W non-membrane bound, spherical structures X a double membrane with many pores Y non-membrane bound, cylindrical structures Z membrane-bound sacs, arranged as a flattened stack Which student correctly matched the numbered function with the appearance of the cell structure?

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

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5

The features of some cells and cell structures that make ATP are listed. has outer boundary membrane and folded inner membrane has peptidoglycan cell wall outside an outer boundary membrane has a double boundary membrane and stacks of inner membranes Which row identifies these components?

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

12. Energy and respiration  →  12.1. Energy

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6

Mitochondria are thought to have evolved from prokaryotic cells that were ingested by an ancestral cell. Which feature have these prokaryotes lost during their evolution into mitochondria?

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

12. Energy and respiration  →  12.2. Respiration

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7

A student carried out the Benedict’s test on a sample and got a negative result. What should the student do to confirm there are no sugars present in the sample?

2. Biological molecules  →  2.1. Testing for biological molecules

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8

The diagrams show three hexoses. C C C C H H OH OH OH H OH H HO C O H H CH2OH C C C C H H OH OH OH OH H H HO C O CH2OH C C C C H OH H H O CH2OH HOH2C In which carbohydrates do these three hexoses occur?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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9

The diagram shows part of the chemical structure of a naturally occurring polysaccharide. O HO COOH OH OH O O O COOH OH OH O O O HO CH2OH HN CH3 O O O HO CH2OH HN CH3 O O O What types of glycosidic bonds are present?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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10

What is the maximum number of water molecules produced when a triglyceride is synthesised?

2. Biological molecules  →  2.2. Carbohydrates and lipids

12. Energy and respiration  →  12.1. Energy

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11

What occurs during the formation of a peptide bond between two amino acids?

2. Biological molecules  →  2.3. Proteins

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

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12

The diagram represents roles of water in living organisms. role of water in living organisms carries dissolved substances temperature control due to evaporation provides a constant environment for aquatic organisms Which roles are dependent upon hydrogen bonds between water molecules?

2. Biological molecules  →  2.4. Water

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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13

The diagram shows a metabolic pathway. reactant enzyme 1 substance X enzyme 2 substance Y enzyme 3 end product What would be the effect of adding a small amount of a non-competitive inhibitor of enzyme 2?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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14

Two enzymes are added to a solution containing a low concentration of a substrate that they can both use. Which statement is correct?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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15

The diagram shows the fluid mosaic model of membrane structure. Structures 1, 2, 3 and 4 are types of molecule. Which types of molecules are always identical?

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

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16

What is the role of G protein in cell signalling?

14. Homeostasis  →  14.1. Homeostasis in mammals

16. Inheritance  →  16.3. Gene control

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17

When a small quantity of phospholipid is added to a test-tube of water and then shaken vigorously, an emulsion is formed by small droplets called liposomes. Which diagram shows the arrangement of phospholipid molecules in a cross-section of a liposome?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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

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18

What are the features of facilitated diffusion?

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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19

Which description of chromosome structure is correct?

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

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

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20

Which processes involve mitosis?

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

11. Immunity  →  11.1. The immune system

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21

A drug has been developed to treat certain types of cancer. It prevents mitosis by binding to the spindle and preventing sister chromatids being separated and moving to opposite poles of the cell. The photomicrograph shows cells in different phases of mitosis. What represents the stages of mitosis that will be able to occur in a cell which is entering prophase when treated with this drug?

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

Some viruses have single-stranded DNA as their genetic material. This DNA molecule has to be folded to fit in the protein coat. Which statements about single-stranded DNA are correct?

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

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23

How many statements are true for semi-conservative replication of DNA in a eukaryotic cell?

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

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24

Part of the nucleotide sequence of an mRNA molecule is shown...

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

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25

External factors change the rate of transpiration, which also affects the water potential gradient of cells in the leaf. Which combination is correct?

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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26

The photomicrograph shows a transverse section through a leaf. ×50 Which features of a xerophytic leaf are visible in this section?

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

7. Transport in plants  →  7.2. Transport mechanisms

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27

Which changes occur as carbohydrates move out of a root cell into a phloem sieve tube?

7. Transport in plants  →  7.2. Transport mechanisms

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28

The photomicrograph shows three white blood cells labelled X, Y and Z. Y Z X Which row correctly identifies these cells?

8. Transport in mammals  →  8.1. The circulatory system

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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29

The graph represents data on blood vessels and blood flow. arteries small arteries capillaries small veins veins key X Y Z Which row correctly identifies the curves?

8. Transport in mammals  →  8.1. The circulatory system

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30

Which components of blood are present in lymph?

8. Transport in mammals  →  8.1. The circulatory system

14. Homeostasis  →  14.1. Homeostasis in mammals

9. Gas exchange  →  9.1. The gas exchange system

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31

What correctly describes the significance of the increase of the red blood cell count of humans who move from living at low altitude to high altitude?

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

8. Transport in mammals  →  8.1. The circulatory system

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32

Which structures of the human gas exchange system are supported by cartilage?

9. Gas exchange  →  9.1. The gas exchange system

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33

Carbon monoxide, nicotine and tar are components of tobacco smoke. Which row correctly describes their effect on a smoker’s body?

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

12. Energy and respiration  →  12.2. Respiration

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34

Which statements about chronic obstructive pulmonary disease (COPD) are correct?

11. Immunity  →  11.2. Antibodies and vaccination

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35

Which of these causative agents of disease can be transmitted by droplet infection?

10. Infectious diseases  →  10.1. Infectious diseases

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36

The table compares total antibiotic use (and the percentage of antibiotic-resistant pneumonia cases (Y) in five countries. country (total antibiotic use / defined dose per 1000 people per day (Y) percentage of penicillin-resistant pneumonia cases Austria Denmark Iceland Spain USA What is supported by the data?

10. Infectious diseases  →  10.2. Antibiotics

18. Classification, biodiversity and conservation  →  18.2. Biodiversity

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37

Which statement about the development of resistance to antibiotics in bacteria is correct?

17. Selection and evolution  →  17.2. Natural and artificial selection

10. Infectious diseases  →  10.2. Antibiotics

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38

A blood cell count can indicate how many white blood cells there are in the blood. Where else in the body are white blood cells found?

8. Transport in mammals  →  8.1. The circulatory system

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39

Myasthenia gravis is a disease that results from the immune system failing to distinguish between self and non-self. Antibodies bind to a component of the junctions between a muscle and its nerve. What correctly describes Myasthenia gravis?

11. Immunity  →  11.1. The immune system

15. Control and coordination  →  15.1. Control and coordination in mammals

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40

A monoclonal antibody, specific for a virus, was treated with an enzyme to break the bonds between the variable and constant regions. The separated variable and constant regions were then added to cells infected with the virus. Which statements are correct?

11. Immunity  →  11.2. Antibodies and vaccination

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