One to four mark questions

One to four mark 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
  • '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
  • 'compare' where you describe the similarities and/or differences between things

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 a steep linear increase for the first three hours 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 '[2 marks]'. It is essential that you give two different answers if a question is worth two marks. Sometimes you can gain a second mark by giving the units in a calculation or stating specific data points, eg during the first two years the number of lions deceased by seven.

You will be expected to write in more depth for three and four mark questions. They might ask you about a process such as the carbon cycle or the method you would use in an experiment.

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


Complete the sentences using the terms below.

pairs, proteins, inherited, DNA, genes

Chromosomes in body cells are found in __________. They are long strands of molecules of __________. Chromosomes have __________ which determine __________ characteristics.

Pairs, DNA, genes, inherited

Sample question 2 - Foundation


In cats, the allele for short hair (D) is dominant to the allele for long hair (d).

A cat with short hair was mated with a cat with long hair. All of the offspring (F1) had short hair.

i) What are the genotypes of the parents? [1 mark]

ii) Complete the Punnett square to show the cross between the cat with short hair and the cat with long hair. [2 marks]


i) Cat with short hair - DD, cat with long hair - dd [1]

The cats will be homozygous as the question states that the offspring all show the dominant characteristic




One mark will be awarded if the gametes were correctly placed in the grid and another for working out the cross correctly.

Sample question 3 - Foundation

Classification of the cow (Bos taurus) and a part classification of the horse (Equus ferus) are shown below.


Complete the classification of the horse in the table above. [3 marks]



Usually spelling is unimportant but if the word is already written on the page eg vertebrates, it is important that spelling is accurate.

In this case as a genus and species are required, it is important that the genus has a capital letter (Equus) and the species a lowercase letter (ferrus).

Sample question 4 - Higher


What is the difference between genotypes and phenotypes? Give an example of each in your answer. [4 marks]

  • genotypes are letters used to determine characteristics [1]
  • BB, Bb, bb for eye colour (accept other suitable examples) [1]
  • phenotypes are physical descriptions using words that describe genotypes [1]
  • so BB and Bb are brown eyes and bb is blue eyes (accept other suitable examples) [1]

Sample question 5 - Higher

In mice the allele for black eye colour (B) is dominant over the allele for red eye colour (b).


What is the phenotype of each of the following mice? [1 mark]

Mouse 1 - BB

Mouse 2 - Bb

Mouse 3 - bB

Mouse 4 - bb

Mouse 1 - BB - black

Mouse 2 - Bb - black

Mouse 3 - bB - black

Mouse 4 - bb - red


i) If mouse 1 and mouse 4 were mated together and had 12 offspring, how many of these would you expect to have black eyes?[1 mark]

ii) Complete the Punnett square below to help you answer. [1 mark]


i) 12 [1]




Sample question 6 - Higher


How does the modern-day use of genome sequencing help us to genetically modify organisms? [3 marks]

Three from:

  • genome sequencing provides us with the sequence of bases in an organism's DNA
  • this allows us to identify specific genes
  • which can be removed using enzymes
  • and then transferred to other organisms during genetic modification