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1

The diameter of living cells varies considerably. Typical diameters are: a prokaryote, such as Streptococcus - 750 nm a eukaryotic cell, such as a white blood cell - 15 µm Given these measurements, the diameter of the white blood cell is how many times greater than the prokaryote?

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

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2

In constructing a plan diagram of a transverse section of a dicotyledonous leaf, which feature should not be included?

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

7. Transport in plants  →  7.2. Transport mechanisms

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3

Membranous sacs containing products of metabolism are formed by the endoplasmic reticulum in cells. Where are these products used?

12. Energy and respiration  →  12.2. Respiration

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4

The diagram shows a graduated slide, with divisions of 0.1 mm viewed using an eyepiece graticule. 90 100 Pollen grains were grown in a sugar solution and viewed using the eyepiece graticule. Diagram 1 shows the pollen grains at first and diagram 2 shows them after four hours. 90 100 90 100 at start after 4 hours diagram 1 diagram 2 What is the growth rate of the pollen tubes?

13. Photosynthesis  →  13.2. Investigation of limiting factors

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

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5

In 1985, a giant bacterium, Epulopiscium fishelsoni, was discovered. Which cell structurewould be present in Epulopiscium enabling biologists to classify this organism as prokaryotic?

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

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6

This molecule is a polymer of reducing sugars. O O OH CH2OH OH O OH CH2OH OH HO O O OH CH2OH OH O O OH OH CH2OH OH Which of the following procedures could be carried out in order to test for the presence of the reducing sugars in this molecule?

2. Biological molecules  →  2.1. Testing for biological molecules

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7

Which correctly matches the functional and structural features of cellulose, collagen, glycogen and triglyceride?

2. Biological molecules  →  2.2. Carbohydrates and lipids

2. Biological molecules  →  2.3. Proteins

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8

Which describes the structure of amylopectin?

2. Biological molecules  →  2.2. Carbohydrates and lipids

2. Biological molecules  →  2.3. Proteins

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9

Which molecule is found in glycogen?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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10

High concentrations of urea break all bonds, except covalent bonds, in protein molecules. Which level of protein structure would remain unchanged when a protein is treated with urea?

2. Biological molecules  →  2.3. Proteins

14. Homeostasis  →  14.1. Homeostasis in mammals

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11

Which bonds are the last to break when an enzyme is heated?

2. Biological molecules  →  2.3. Proteins

3. Enzymes  →  3.2. Factors that affect enzyme action

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12

During the production of apple juice, enzymes are used to break down the components of the cell walls. Which carbohydrate will be produced by this hydrolysis?

2. Biological molecules  →  2.2. Carbohydrates and lipids

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13

The rate of enzyme catalysed reactions in human cells is regulated. Which of the following may be involved in such regulation?

3. Enzymes  →  3.2. Factors that affect enzyme action

3. Enzymes  →  3.1. Mode of action of enzymes

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14

The diagrams show two kinds of molecules found in cell surface membranes. Which part affects the fluidity of the membrane?

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

7. Transport in plants  →  7.2. Transport mechanisms

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15

The graphs show the rate of uptake of sugars by a culture of animal cells, under different conditions. temperature / °C air bubbled through the culture 3-carbon sugar 6-carbon sugar rate of uptake temperature / °C nitrogen gas bubbled through the culture 3-carbon sugar 6-carbon sugar rate of uptake How are the sugars taken up by the cells when air is bubbled through the culture?

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

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

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16

Which process allows the movement of molecules that are too large to pass in through a cell surface 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

Which structure organises spindle formation during mitosis in animal cells?

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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18

Which processes involve mitosis?

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 graph represents the changes in the quantity of DNA present in one nucleus at different stages in the life cycle. relative DNA content time egg fertilisation X Which stage takes place at X?

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 type of sugar and bonds are found in a DNA molecule?

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

2. Biological molecules  →  2.3. Proteins

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21

A length of double-stranded DNA contains 120 nucleotides and codes for polypeptide X. What is the maximum length of polypeptide X?

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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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 occurs in the apoplast and symplast pathways?

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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24

In an animal cell, which process is dependent upon cell surface area and which process is dependent upon cell volume?

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

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25

The diagrams show transverse sections of parts of a plant. root stem leaf In the cross sections, what do 1, 2, 3, 4, 5 and 6 represent?

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

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26

Land flooded by the sea is not suitable for growing plants long after the salty flood water has drained away. The diagram represents a transverse section through a part of the root of a plant. xylem cortex soil water Which values of water potential (kPa) in the xylem and soil water help to explain why the land flooded with salty water is unsuitable for growth of plants?

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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27

In mammals, some carbon dioxide is transported by red blood cells in combination with haemoglobin. What is the product of this combination?

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

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28

A red blood cell, entering the right side of the heart, passes by or through the following structures. atrioventricular valve semilunar valve right atrium right ventricle sinoatrial node In which order will the red blood cell pass the structures?

8. Transport in mammals  →  8.3. The heart

8. Transport in mammals  →  8.1. The circulatory system

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29

What correctly describes the cause and effect of carcinogens on lung tissue?

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

9. Gas exchange  →  9.1. The gas exchange system

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30

What is a correct description of part of the respiratory system?

9. Gas exchange  →  9.1. The gas exchange system

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31

Which statement describes the vital capacity of a human lung?

12. Energy and respiration  →  12.1. Energy

9. Gas exchange  →  9.1. The gas exchange system

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32

Which statement explains why people suffering from malaria and people suffering from tuberculosis can both live in northern Europe, but only tuberculosis can be passed on to other people there?

10. Infectious diseases  →  10.1. Infectious diseases

11. Immunity  →  11.2. Antibodies and vaccination

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33

The diagram shows the effects of the antibiotics streptomycin and penicillin on the bacterium Escherichia coli. P S S colonies of E. coli petri dish into which nutrient agar containing E. coli has been poured disc of filter paper soaked in a solution of streptomycin P disc of filter paper soaked in a solution of penicillin What can you deduce about the response of E. coli to the effects of the antibiotics?

10. Infectious diseases  →  10.2. Antibiotics

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

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34

The diagram refers to properties of diseases. Which area of the diagram refers to properties that are common to both tuberculosis and cholera?

10. Infectious diseases  →  10.1. Infectious diseases

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35

What causes the measles vaccine to be less effective in children from less economically developed countries?

11. Immunity  →  11.2. Antibodies and vaccination

10. Infectious diseases  →  10.1. Infectious diseases

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36

What is the function of the plasma cells during an immune response?

11. Immunity  →  11.1. The immune system

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37

The graph shows the amount of antibody produced in response to an antigen. concentration of antibodies in the blood first exposure to an antigen time in days From the graph, which statement is correct?

11. Immunity  →  11.2. Antibodies and vaccination

11. Immunity  →  11.1. The immune system

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38

What limits the number of trophic levels in a food chain?

18. Classification, biodiversity and conservation  →  18.2. Biodiversity

13. Photosynthesis  →  13.2. Investigation of limiting factors

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39

The following are definitions of three ecological terms. all of the organisms and their environment group of individuals of one species living in an area all of the organisms living in a habitat What are the correct definitions of a community and a population?

18. Classification, biodiversity and conservation  →  18.1. Classification

18. Classification, biodiversity and conservation  →  18.2. Biodiversity

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40

The diagram shows the circulation of nitrogen in nature. nitrogen in the air nitrate in soil nitrite in soil ammonium nitrate in fertiliser NH4 + in soil organic nitrogen in legumes lightning NO plants animals What is correct?

7. Transport in plants  →  7.2. Transport mechanisms

9. Gas exchange  →  9.1. The gas exchange system

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