"The questions you are asked in an interview for a position as a scientist will depend greatly on field of science you intend to work in. Generally, interviewers will be interested in your formal education, field of study and specialization, work, internship, and research experience, scientific writing skills, and interest in the subject matter. Expect to be asked technical questions that pertain to the knowledge needed to perform the duties of the job. While there are some positions open to scientists who possess associates' or bachelors' degrees, most jobs will require you to have at least a masters' degree with the majority requiring you to have a doctorate."
Describe past research and what you want to research in the future.
Best if these answers involve cutting edge stuff.