Both University interviews and job interviews are based on the same premise, to see how your mind works and how well suited you are to the task at hand.
There are of course things you can do to prepare. Being knowledgeable about the area in question is certainly useful but getting the right answer is not necessarily all that matters. Broken down your thoughts are a collection of electrical impulses picking up speed when they travel over neurons that have been used more than others. The route the signal follows often reveals more than the end product arrived at. Less scientifically put the journey taken in arriving at your answer can hold more answers to the bigger questions that the interviewee is looking for. In most scenarios they are looking for how well you can speak on the topic and how excited you are by it. Another applicant may have read every piece of literature on the topic in question but if they cannot share their own view about it, their preparation work holds much less gravitas. Being confident in how you deliver whatever amount you know is much more poignant.
Many interview techniques cover the same ground, introducing yourself well sets the tone of the interview, holding eye contact highlights your social skills and speaking smoothly and calmly shows you can control your nerves. It is the sum of multiple points that determines how well an interview has gone, not only whether you gave the right answer to the questions.
Iain McGilchrist in his book “The Master and his Emissary” postulates that in the Western world, the left hand side of the brain regards itself as the Master, making the right hand side of the brain its Emissary. The left hemisphere is focused on the detail, which as a result tricks it into thinking it knows everything. However, without the right hemisphere, the information obtained means nothing because the right side computes the details and makes it mean something in the wider picture. The narrow tunnel vision of the left hand brain is unaware of the service the right hand offers. Using this hypothesis and applying it to an interview, being caught up in the details you often cannot see the bigger picture. It is important to remember that the selection criteria for both University and job offers are concerned with potential.
Neither a University nor a job expects you to have the answer to everything. If given an offer you will learn in both arenas. What both of them do expect is a willingness and an eagerness to learn and that, what they teach you and that which you will acquire through your own experience will be beneficial to them. It is a symbiotic relationship, your potential and their need for the right person should provide you with some comfort. This point may be even more relevant for a job offer, that they need you as much as you need them. For most people, learning the art of how to interview begins at University level, once mastered a job interview is no longer a daunting prospect but an exciting one in which you get to showcase your talents.