Key Stage 3 Science Book 3 Assessments
1. Which of the statements is true? [1 mark] b)
Difficulty level: moderate
Skill level: knowledge
2. What type of correlation is shown when, as one quantity increases, the other also increases? [1 mark] b)
Difficulty level: moderate
Skill level: knowledge
3. Which scientist first used X-ray crystallography to show that DNA has a helical structure? [1 mark] d)
Difficulty level: difficult
Skill level: knowledge
4. A plant grower transfers the pollen from a plant producing small, sweet-smelling flowers onto a plant producing large flowers without any scent. What type of flower would the breeder hope to produce? [1 mark] d)
Difficulty level: moderate
Skill level: application
5. A young girl has the same colour eyes and same shaped nose as her mother, and has freckles and red hair like her father. Which statement explains why the girl has some features in common with her mother and other features in common with her father? [1 mark] b)
Difficulty level: moderate
Skill level: evaluation
6. A scientist is presenting a speech to share his theory about how mass extinction may have been caused in the past. He suggests that a huge volcanic eruption caused extinction of dinosaurs. Which of the following statements could explain why some other organisms were able to survive such a volcanic eruption? [1 mark] a)
Difficulty level: difficult
Skill level: evaluation
© HarperCollinsPublishers 2014

Key Stage 3 Science Book 3 Assessments
7. A scientist is following a recipe to extract DNA from liver cells. Unfortunately, the steps and the reasons for each have been mixed up. Match each step in the process of extracting DNA to its purpose
[1 mark]
Sample of tissue taken
Tissue is ground
To provide a sample of cells
Cells are broken open
Salt and cleaning agent added
Ethanol added
Breaks down fats and protein
Solidifies the DNA
Difficulty level: moderate
Skill level: application
8. Choose two correct statements about a sperm cell. [1 mark] b), c)
Difficulty level: moderate
Skill level: knowledge
9. Describe and explain an example of a natural cause of extinction. [2 marks]
(the answer should contain one factor and its explanation)
1) Climatic heating and cooling [1 mark] leads to temperature changes to a value that the species cannot survive in [1 mark]
2) Changes in sea level [1 mark] destroy the habitat of a species [1 mark]
3) Asteroid impact [1 mark], and the collision kills species/damages habitat of a species [1 mark]
4) Disease [1 mark] which kills all organisms of a species [1 mark]
Difficulty level: moderate
Skill level: knowledge
10. Tropical rainforests and coral reefs are the ecosystems with the greatest biodiversity on the planet.
Explain how an ecosystem with high biodiversity is more able to survive changes than an ecosystem with low biodiversity. [2 marks]
(the answer should contain the following)
1) Greater chance of one of the species being able to adapt to any change
2) Food webs are affected less/less chance of food sources disappearing
Difficulty level: moderate
Skill level: knowledge
© HarperCollinsPublishers 2014

Key Stage 3 Science Book 3 Assessments
11. DNA profiles can be stored on a database. Explain two advantages and two disadvantages of having a national DNA database with DNA profiles of everyone in the country. [4 marks]
(the answer should contain two advantages and two disadvantages)
1) Advantage: it could help to catch criminals by detecting who was present at a crime scene
2) Advantage: it could prove the innocence of previously-convicted people, by detecting whether or not they were at a crime scene
3) Disadvantage: prospective employers/insurance companies etc. could use information to tell whether a person is likely to get ill (or similar)
4) Disadvantage: it is difficult to keep patient confidentiality
5) Any other plausible advantages or disadvantages.
Difficulty level: difficult
Skill level: knowledge
12. A child visits a museum and sees some stuffed birds from history. He notices that a gull that lives in a colder environment has a much thicker plumage of feathers than one that lives in a warmer environment. Explain how natural selection has led to the thicker plumage in the bird from a colder environment. [2 marks]
(the answer should contain two of the following)
1) In colder environments, birds with thicker plumage (feathers) are more likely to survive
2) Birds with thicker plumage are more likely to breed and pass on genes
3) More birds are produced with thicker plumage
Difficulty level: moderate
Skill level: application
© HarperCollinsPublishers 2014

Key Stage 3 Science Book 3 Assessments
13. A single strand of DNA has been screened in a research laboratory. The order of bases is shown below.
Explain why these results are not representative of the whole DNA molecule and comment on the rest of the molecule. [2 marks]
(the answer should contain two of the following)
1) DNA molecule is double stranded
2) The other strand would have sequence TGGCAATCCG
3) This is only a small section of DNA; the entire molecule is likely to be longer
Difficulty level: moderate
Skill level: evaluation
14. The photo shows variation between lizards living in rocky mountains (left) and in grassy regions
(right).
Explain how natural selection would affect the population of green lizards if they lived in the rocky mountains.
[2 marks]
(the answer should contain two of the following)
1) The green lizard population would decrease [1 mark] OR green lizards would become outnumbered by grey lizards [1 mark]
2) The green lizard would be less well camouflaged in mountains, so more likely to be eaten [1 mark] OR the grey lizard is better camouflaged and less likely to be eaten [1 mark]
3) The grey lizard would be more likely to survive to reproduce to pass on its genes
Difficulty level: difficult
Skill level: evaluation
© HarperCollinsPublishers 2014

Key Stage 3 Science Book 3 Assessments
15. A brother and sister are both left-handed. However, they have different eye colour – the boy has brown eyes and the girl has blue eyes. Explain how fertilisation has led to this difference in eye colour.
[4 marks]
(the answer should contain four of the following)
1) Each child inherits half of their chromosomes from their mother and half from their father
2) Which chromosome of each pair is passed on is random
3) Each child inherits a random mix of chromosomes from their mother and father
4) Reference to an example of the brother and sister inheriting the same one-of-a-pair of chromosomes
(gene for left-handedness) or different one-of-a-pair (gene for eye colour)
5) Each egg and sperm contain only one of each pair of chromosomes, which one of each pair is random
Difficulty level: moderate
Skill level: application
16. A man who was adopted as a child is trying to trace his natural parents. Suggest two features that the man would have in common with either one of his natural parents. Explain why some features would not have been inherited from his parents, giving an example. [4 marks]
(the answer should contain four of the following)
1) Two inherited features such as blood type, natural eye colour, natural hair colour, inherited disease
(one mark per feature)
2) Other variation is due to environment, not genetics
3) Example such as scar, hair length, missing teeth (or other sensible example)
Difficulty level: difficult
Skill level: application
© HarperCollinsPublishers 2014