Animal coordination and control - 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 lose 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.

Edexcel questions courtesy of Pearson Education Ltd.

Sample question 1 - Foundation

Graph showing the internal temperature of a fish and an otter when the external temperature changes

The graph shows how the internal temperature of a fish and an otter changes when the external temperature changes.

Explain why it is important that the temperature of the otter is maintained at about 37°C. [2 marks]

  • otters need an optimum temperature of 37°C as this is the optimum temperature for enzyme action [1]

Plus one point from:

  • because at lower temperatures enzymes work too slowly
  • because at higher temperatures enzymes are denatured


Sample question 2 - Higher


The doctor diagnosed a person with an underactive thyroid gland.

Explain why an underactive thyroid could cause this patient to feel tired and have an increased body mass. [6 marks]

An explanation should include these points:

  • the thyroid gland produces thyroxine [1]
  • thyroxine helps to regulate metabolic rate [1]
  • an underactive thyroid would cause less thyroxine to be produced [1]
  • metabolic rate drops [1]
  • they feel tired because less energy being released from food [1]
  • more fat storage so the person gains body mass [1]