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

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 an increase in the mass of potato cylinders. 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


Antibodies are produced by white blood cells to bind with antigens on the surface of pathogens. Scientists have designed monoclonal antibodies for various uses. Describe some of these uses. [6 marks]

  • HCG hormone is present in the urine of pregnant women [1].
  • Monoclonal antibodies that bind with HCG are present on the ends of pregnancy test sticks [1].
  • When pregnant women urinate on these sticks that antibodies bind with the antigen in the hormone and indicate pregnancy [1].
  • Monoclonal antibodies can also bind with antigens on cancer to diagnose the presence of tumours [1].
  • They can also take drugs that have been attached to them to tumours to treat them [1].
  • The can also help your immune system attack cancers [1].
  • They can also bind to and diagnose HIV/AIDS, herpes and chlamydia [3].

Sample question 2


Describe the effects of specific virus infections of a plant and an animal. Give the names of the viruses in your answer. [6 marks]

Part 1 - plant

  • The tobacco mosaic virus infects tobacco and other closely related species [1].
  • It infects the chloroplasts of plant leaves [1].
  • It changes their colour from green to yellow or white in a mosaic pattern [1].
  • It can also make leaves crinkled or curled up [1]. This reduces the plant’s ability to photosynthesise, which reduces the crop yield of farmers [1].

Part 2 - animal

  • HIV stands for human immunodeficiency virus [1].
  • It is transmitted by body fluids, often during unprotected sex and injecting drugs using dirty needles [1].
  • Immediately after infection, infected people often suffer mild flu-like symptoms [1].
  • AIDS stands for acquired immune deficiency syndrome [1].
  • Months or years after infection the HIV virus becomes active and HIV turns into AIDS [1]
  • It starts to attack the patient’s immune system [1].

Sample question 3


Doctors are now prescribing fewer antibiotics to reduce the evolution of antibiotic resistant bacteria. Describe the process of evolution of antibiotic bacteria. [6 marks]

  • In every population there is variation, so some bacteria are resistant whilst others aren't [1].
  • The individuals (in this example, the bacteria) with the most advantageous characteristics are more likely to survive and reproduce [1].
  • So those that have the gene for antibiotic resistance have an advantage [1].
  • This is survival of the fittest [1].
  • Because of inheritance, the offspring of those with the advantageous characteristic are more likely to have it [1].
  • This process is repeated over many generations until most of the bacteria are now antibiotic resistant [1].

Sample question 4


Describe how the classification of viruses, bacteria and fungi is different. [4 marks]

  • Viruses are not alive because they do not complete all of the seven life processes [1].
  • Viruses are not classified as living species, but strains that replicate rather than reproduce [1].
  • Bacteria and fungi do complete the seven life processes are so are alive [1].
  • Bacteria do not have a nucleus as so are prokaryotes [1].
  • Fungi do have a nucleus so are eukaryotes [1].
  • Bacteria contain plasmids – small circles of DNA [1].