Oxford Biology Interview Questions

Do you have an Oxford interview coming up? Our list of Oxford Biology interview questions contains real questions from past interviews as well as an example question with a detailed worked solution from an Oxbridge interview tutor.

Our advice is that start by reviewing the worked solution first to see the type of thinking admissions tutors want to see from interviewees. Then try some of the questions listed below.

However, we recommend that you use these to practise ways of approaching questions rather than trying to write ‘model’ answers and memorise them. It’s very unlikely that you would be asked one of these exact questions in your Oxford Biology interview. Even if it were to come up, then Oxford tutors can tell if you’re reciting a prepared answer and they mark it down.

Looking for more Oxford interview questions? We have real past questions for many Oxbridge courses, available completely free.

Sample Interview Question and Worked Solution

Is this disease dominant or recessive?

This Oxford Biology interview question is really testing your abilities to think logically, since it doesn’t actually require any scientific knowledge, other than an understanding of basic Mendelian genetics (covered on most GCSE courses). Being able to think logically is a prerequisite of studying science and is therefore often tested at interview. Working through this question helps to illustrate how to structure questions that are not based on pre-existing knowledge, but are instead designed to see how you think.

The key to answering such a question is not to jump in with an answer – it is highly unlikely that you will be given a question like this in an Oxbridge interview if a definitive answer can be reached very quickly. It is also very important to show your interviewer your thought process – including ‘exploratory thoughts’ which may, or may not, prove fruitful. There is no discredit in abandoning an unproductive line of thought; indeed, showing that you have a sense of when it becomes clear that it IS unproductive is just as important as alighting on a productive line of thought straight away.

So where should you begin with a question like this? There are of course a number of different ways of tackling the question. The question is asking whether the disease is dominant or recessive. So an appropriate first stage would be to consider whether the genetic tree diagram makes sense if the disease is dominant; and to do this using a structured method. The first question you would be asking is: does the genetic tree diagram make sense if the disease is dominant? In order to work this out, we must begin by establishing what the different genotypes in the tree will be. Let’s label the dominant allele A and the recessive allele a. If the disease is dominant, normal individuals will therefore have genotype aa. Sufferers on the other hand could have genotype AA or could have genotype Aa. We then begin working through the tree. Again, try pausing here and working from Generation 1 down the tree to see whether it makes sense for the disease to be dominant.

Working through the tree should yield the following conclusions:

• In generation 1 the man is AA/Aa and the woman is aa.
• The offspring in generation 2 are both sufferers. Since they must have received a recessive (a) allele from their mother, and they are sufferers, we know that their exact genotype must be Aa. (At an additional level of analysis we could note that if the man in generation 1 was AA we would have expected 100% Aa in the offspring. If on the other hand the man in generation 1 was Aa we would expect only 50% in the offspring. It is therefore more likely that the first man’s genotype was AA.
• All of the offspring in generation 3 are therefore born from a cross between Aa and aa. We would therefore expect 50% of them to be sufferers. In fact, 100% are sufferers. This is not the most likely outcome from such a cross; but it is still possible that the disease could be dominant.
• The offspring in generation 4 have also all been born from a cross between Aa and aa, which would be expected to give 50% of sufferers. Here, 6 out of 8 of the children are sufferers. This is consistent with the disease being dominant.
• The same again applies to the offspring in generation 5 as to the offspring in generation 4.
• Conclusion: It is possible that the disease is dominant.
• Does the genetic tree diagram make sense if the gene is recessive? Again, it is important to begin by considering what the genotypes would be if the disease were recessive. Sufferers would have genotype aa, whilst non-sufferers could be AA or Aa (carriers).
• In generation 1 the man is aa and the woman is Aa/AA.
• The offspring in generation 2 are both sufferers. The woman in generation 1 therefore MUST have had phenotype Aa in order for the offspring to receive two recessive alleles, and all the offspring in generation 2 have genotype aa.
• The offspring in generation 3 are also all sufferers. The two individuals who marry into the family therefore MUST have had phenotype Aa. (Note that again we would have expected 50% to be sufferers instead of 100%. Therefore the ratios observed are of the same likelihood whether the disease is dominant or recessive and do not help to choose between them.)
• There are sufferers in generation 4. Therefore again the individuals that marry into the family MUST have phenotype Aa.
• There are sufferers in generation 5. Therefore the individuals that marry into the family MUST have phenotype Aa.

Conclusion: It is possible that the disease is recessive: however, this requires making the assumption that every individual marrying into the family is a carrier of the disease. The above would therefore form a well-structured answer to the question posed; though such an answer would often be reached with guidance from the interviewer.

This answer raises the question of how much of an assumption it is to assume that the individuals marrying into the family are carriers of the disease; which creates a more biological aspect to this question. Try and think about whether this is a big assumption to make (and therefore highly unlikely to be valid) before reading the following.

This question requires you to think about why there are carriers present in the population. To decide whether it is a big assumption to make would require some knowledge of the disease. If the disease is very rare and having the gene for the disease is in no way beneficial from an evolutionary perspective then assuming such a prevalence of carriers would be a big assumption to make. However, there are diseases where being a carrier is very beneficial from an evolutionary perspective. The most common example of this is sickle cell anaemia. In sickle cell anaemia, changes in the carriers’ red blood cells means that the malarial parasite cannot complete part of its life cycle. Therefore if someone in a malaria-endemic population is reproducing, it could in fact be argued that it is more likely that they are a carrier, since if they weren’t a carrier they would have had an increased risk of malaria and an increased risk of not reaching child-bearing age.

This illustrates how pre-existing knowledge can be applied to new situations in the science interview questions faced at Oxbridge.

Past Oxford Biology Interview Questions

The following questions have appeared in interviews for Biological Sciences at Oxford in recent years. We recommend that you use these questions to a) familiarise yourself with the types of questions asked and b) practise thinking laterally about your subject.

It’s very inadvisable to try to memorise answers to these specific Oxford Biology interview questions. Firstly because the exact questions are very unlikely to recur in your interview, and secondly because Oxford interviewers can spot prepared answers and do not reward them. They want you to think on your feet and respond to difficult questions in real time, not parrot a script that you learned before the interview.

• Which area of biology interests you most?
• How would you define science?
• Why does a cat have tortoiseshell fur?
• How could you test if a bird never landed?
• Why is this coral (pictured) green?
• Given a skull and asked to deduce which animal it was from.
• Asked about a topic I found interesting in my personal statement.
• Asked about wingspan in insects and birds their relation to oxygen levels.
• Describe the landscape.
• Imagine a quarry was going to be set up- as a biologist what might you be concerned about? Given financial limitations, how would you prioritise species to conserve?
• Cacti are able to open their stoma at night- why might this be?
• What triggers the stomata to open normally?
• Can you suggest a mechanism for photosynthesis during the night?
• Given 2 large seed pods – asked to explain their differences in appearance and how this affected their dispersal and growth strategies, as well as genetic diversity.
• Can you tell me about this cactus?
• Why did this section of a tree have smaller rings in its trunk?
• Asked about the effect of removing light triggers from mice and the effect on their diurnal rhythms.
• Do animals lie?
• How might these different plants reproduce? (with pictures)
• Would a rainforest have a different number or similar number of trophic levels than British countryside?
• Given a sample of coral and asked what I could work out from the piece and my knowledge of coral.
• Why is genetic variation in a species important?
• Why are there errors in DNA replication, and why are errors important?
• Describe how segregation distortion genes work.
• Where might you find a simple bacterium? (In the context of a discussion about an artificial cell.)
• How might climate and seasons affect the infection rate of a disease?
• What might a peak in infection rate every 10 years indicate?
• Why didn’t sea turtles go extinct like lots of other species? How would you go about conserving the species now?
• If a plant is left in warm, sunny conditions, its photosynthetic output increases. If it is taken into a lab (so it is now out of the sun) its photosynthetic output remains high. Why?
• Why do you think malaria isn’t present in Europe?

For more practise, explore our Oxford Biochemistry interview questions as many will be relevant.

How Dukes Plus Can Help

We hope you found practising with these Oxford Biology interview questions useful.

If you’d like specialist coaching for your Oxford interview, our Oxford interview tutoring includes highly realistic full mock interviews plus feedback from our expert team of Oxford-graduate tutors. Some of our packages also include a session with a former admissions tutor at Oxford – someone with direct experience of interviewing candidates for an Oxford college.