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Which characteristic do all living organisms show?
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The diagram shows some animal cells, as seen under the microscope. What will be present at X?
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Each of the diagrams shows an area of cytoplasm.
Which is from a prokaryote?
505
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533
The diagram shows a section through a root.
What are the levels of organisation of the labelled structures?
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Which characteristics are correct for both osmosis and diffusion? [Table_1]
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535
Which diagram shows the structure of DNA?
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506
The graph shows how enzyme activity is affected by temperature.
How can the change in activity between 40°C and 55°C be explained?
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542
Four test-tubes are set up as shown. Which test-tube contains the most carbon dioxide after one hour?
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The graph shows daily carbon dioxide uptake and transpiration by the plant *Agave americana*. The plant is adapted to live in very dry conditions.
What can be concluded from this graph?
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In plants, which ions are used to make amino acids?
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The following symptoms can be caused by a dietary deficiency:
• bone pain
• dental problems
• fragile bones
• skeletal deformities
A lack of which nutrient is most likely to cause these symptoms?
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Statements 1–4 describe stages in the development of cholera.
1. Chloride ions are secreted in the gut.
2. Osmosis causes water to move into the gut.
3. The infected person becomes dehydrated.
4. Toxins are produced by the pathogenic bacteria.
What is the correct sequence of the four stages?
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526
The diagram shows a human tooth.
Which statement best describes the function of this tooth?
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The graph shows the effect of pH on the activity of three different enzymes.
The table shows the pH of different parts of the alimentary canal.
[Table_1]
Which enzymes in the graph are likely to be protease enzymes?
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The diagrams show cross-sections through a root and a stem.
Which labels are correct?
510
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572
Which processes are used by root hairs to take up ions and water?
[Table_1]
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Which of the following increases transpiration?
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The diagram shows a human blood cell.
What is its function?
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What is a disease-causing organism called?
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Which is a function of the cartilage in the trachea?
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Which is the equation for anaerobic respiration in yeast?
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508
A longitudinal section of the kidney and some associated structures have been labelled. Which labelling is correct?
512
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566
The steps to produce a reflex action where the hand is withdrawn from a hot object are shown.
1. Nerve impulses pass from the sensory neurone to the relay neurone.
2. Nerve impulses pass from motor neurone to the effector.
3. Nerve impulses pass from the receptor to the neurone.
What is the correct sequence of steps?
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556
How many different kinds of cone receptor and rod receptor are there in the human retina?
[Table_1]
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526
What is the result of the release of adrenaline? [Table_1]
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Dianthus flowers can be one of three different colours: red, pink or white.
A red flower is always homozygous and a white flower is always homozygous. Pink flowers are heterozygous.
If a red and a white flower are crossed, what percentage of the offspring will be pink?
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An alligator has 32 chromosomes in each of the cells of its nose. How many chromosomes will an alligator zygote contain?
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Which hormone is produced by cells in the placenta of a developing fetus?
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The diagram shows four types of birth control device.
Which is not a barrier method of contraception?
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Which blood component is destroyed in people who are HIV positive?
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What are stem cells?
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The list shows the diploid number of chromosomes of four organisms.
fruit fly 8
human 46
potato 48
garden pea 14
What is the correct chromosome number of a male sex cell in each of these organisms?
[Table_1]
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Which of these is a population?
1 all the insects in a rainforest
2 all the tigers in a rainforest
3 all the kapok trees in a rainforest
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The number of bacteria resistant to antibiotics is increasing.
What has contributed to this situation?
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The processes listed in 1–4 will affect the concentration of carbon dioxide in the atmosphere.
1. increased deforestation
2. increased forestation
3. decreased fossil fuel combustion
4. increased fossil fuel combustion
Which processes would increase the concentration of carbon dioxide in the atmosphere?
543
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514
The graph shows the changes in the populations of predator and prey over a period of time. Which point on the graph shows a decrease in predator population?
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511
Which is a reason for using bacteria in biotechnology?
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Why is yeast used in breadmaking?
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The graph shows the levels of dissolved oxygen and mineral ions in a river.
At which point does raw sewage enter the river?
[Graph shows levels of dissolved oxygen and mineral ions]
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