Six-mark questions

Six-mark questions are often the questions that people find the most difficult. In all longer answer questions, but especially the six-mark ones, 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.

Six-mark questions will start with command words such as 'describe' 'evaluate' 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 confusing. 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 the pH of milk decreases. It does this because…

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

The number of marks per question part is given in this form '[6 marks]'. It is essential that you include as many different points in your answer as possible. However, it is not simply the case that listing six different points will always gain six marks in a six-mark question as the way that you structure your answer will also be considered.

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


Describe the similarities and differences between plant and animal cells. [6 marks]

Possible content to be included (additional content must be scientifically correct and relevant):

  • they are both eukaryotic so have a nucleus
  • they both possess:
    • cell membranes to control what enters and exits a cell
    • cytoplasm where reactions occur
    • ribosomes where proteins are made
    • mitochondria where respiration occurs
  • plant cells additionally have:
    • chloroplasts where photosynthesis occurs
    • a permanent vacuole filled with sap
    • a cell wall made of cellulose for support

1-2 marks - Description is focussed on either animal or plant cells, but comparisons are not made between the cell types.

3-4 marks - Some general description of plant and animal cells included, but answers are not written in a logical sequence. Focus on only similarities or differences or on only one similarity and difference.

5-6 marks - Detailed description of both animal and plant cells using a logical structure. Comparisons made between a range of features including both the similarities and differences.

Sample question 2 - Foundation


Compare and contrast diffusion and active transport. [6 marks]

Possible content to be included:

  • diffusion is the net movement of molecules from an area of high to lower concentration
  • active transport is the net movement of molecules from an area of low to higher concentration
  • diffusion is a passive process and does not require energy
  • active transport is an active process and so does require energy
  • diffusion occurs down a concentration gradient
  • active transport occurs up a concentration gradient
  • one mark for suitable example of diffusion, eg Oxygen diffuses from the alveoli into the blood in the lungs
  • one mark for suitable example of active transport, eg Plants use active transport to absorb nitrates from the soil

1-2 marks - Answers are limited to either comparing or contrasting rather than both, and connections are not made. Statements are occasionally supported by limited evidence.

3-4 marks - Several features are compared and contrasted with some understanding of the processes demonstrated, but there are some inaccuracies. Some statements are supported by evidence.

5-6 marks - Many features are compared and contrasted, and presented in a logical and well balanced way. Connections are made between ideas. Statements are supported by evidence throughout.

Sample question 3 - Higher


Explain the lock and key model of enzyme action, including how they are denatured. [6 marks]

Possible content to be included:

  • the key is the enzyme and the substrate is the lock
  • the key is specific for the lock like an enzyme is for its substrate
  • extremes of pH or temperature denature enzymes
  • this alters the shape of the active site
  • so the key will no longer fit into the lock
  • the substrate can no longer be broken down or joined together

1-2 marks - Describes and explains one or two aspects of the model but without detail. The explanation has little structure or logical progression.

3-4 marks - Explains several aspects of the model, demonstrating understanding but with some inaccuracies. The explanation is mostly written in a clear, logical structure.

5-6 marks - Explains many aspects of the model demonstrating accurate, detailed understanding throughout. The explanation is well-developed and is clear and logical.