Linking questions

Linking questions span different topics. In linking questions, it is important that you plan your answer and not just rush into it. After all, you would plan an essay or short story before starting. Without a plan it is easy to stray away from the key point and loose marks, get steps in a process in the wrong order or forget key bits of information. Remember to write your answer in full sentences, not bullet points.

One way to answer linking questions is to follow these steps:

  1. Identify exactly what the question is asking (perhaps by underlining key parts)
  2. Identify what the link between the two parts of the question is
  3. Make a short plan of these links (which will form the basis of your answer)
  4. Include as much information as you can to obtain full marks (see below).

The number of marks per question part is given in this form '[4 marks]'. It is essential that you give four different answers if a question is worth four marks. Sometimes you can gain an additional mark by giving the units in a calculation or stating specific data points, eg after twenty-four hours the pH of the milk at room temperature had decreased by 1.2.

Linking questions will start with command words such as 'describe' or 'explain'.

Some command words are easy to understand such as:

  • 'calculate' or 'determine' for maths questions
  • 'choose' for multiple choice questions
  • 'complete' to fill in a gap in a table or graph
  • 'define' to give the meaning of an important word
  • 'suggest' where you use your knowledge in an unfamiliar situation

The command words 'describe' and 'explain' can be confused. If you are asked to describe a graph, you will be expected to write about its overall shape, whether it is linear or curved, the slope of gradients etc. If you are asked to explain why a pattern or trend is seen in a graph, you will be expected to use your science knowledge not just say what you see (which is a description), eg the graph shows that the biodiversity is lower on the school field. This is because…

Explain how and why questions often have the word 'because' in their answer. Describe questions don't.

These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.

Sample question 1 - Foundation


i) The volume of milk produced by a herd of cows was recorded each month for a year. In the winter months, the cows are kept indoors in a large barn. The cows are fed the same quality and quantity of food each month. Suggest why the volumes of milk varied during the winter months. [1 mark]

ii) During the summer months, the farmer noticed that the volume of milk produced by the cows varied depending on which fields on the farm the cows were grazing on.

He divided the cows that produced 6501-7000 litres of milk per year into two groups. One of these groups grazed on a field by the river and the other on a field on the hill.

The graphs below show the results.

Graphs showing the volume of milk produced depending on the location

Explain the differences in the results shown in graphs [2 marks]

iii) When the farmer breeds from his cows he uses a method called artificial insemination (AI). The sperm are introduced into the cows mechanically rather than by using a bull directly.

How does this information suggest that AI is a method of sexual reproduction? [1 mark]

i) Cows produce more milk in the winter months because they are kept indoors. They are warmer so spend less energy on body heat. [1]

ii) River field cows' milk production is higher [1]

Because there are environmental differences [1]

This is a linked mark question. This means the second mark will only be awarded if the first mark has been given.

iii) There are two parents, we know this as sperm are used from a bull. [1]


The table below shows the milk composition of five breeds of dairy cattle.

BreedFat (g/l)Protein (g/l)Milk sugar (g/l)
Brown Swiss3.803.184.80

Milk from which breed of cattle would you recommend to a person suffering from heart disease? Give a reason for your answer. [2 marks]

Holstein [1] - it contains the least fat [1]

This is a linked mark question. This means the second mark will only be awarded if the first mark has been given.

The mark would not have been awarded if the answer said 'it has low fat content' because it is not specific enough.

Sample question 2 - Higher


Describe how mutations in DNA are caused and explain their possible effects. [6 marks]

Six from:

  • mutations are changes in the DNA sequence of an organism
  • they can be insertion, deletion, substitution or inversion of base pairs
  • this can be advantageous, disadvantageous, or have no effect
  • mutations are caused at random, or by ionising radiation and mutagenic chemicals (carcinogens)
  • rapid cell growth of mutated cells can form cancerous tumours
  • benign tumours grow slowly, are easily removed and do not invade other parts of the body
  • malignant tumours grow rapidly, are more difficult to remove and do invade other parts of the body