Undergraduate Anatomy and Physiology (A&P) courses are gateway courses nursing and allied health students must pass before progressing through their academic programs. Many students need to retake the course to receive grades acceptable to progress in their programs, but identifying students at risk of failure may help instructors extend support. In this study, we examined self-efficacy and science identity as potential predictors of student success in these courses, and, by extension, a potential way to identify students at risk of failing. We found that science identity, and not self-efficacy nor completion of science prerequisite courses, explained the most variance when predicting A&P final grade in hierarchical regression. Additionally, we interviewed a purposive sample of students retaking the course to explore their experiences and perceptions of these constructs in A&P over multiple enrollments. Students retaking the course described their experiences of being "biology people" in their interviews, further suggesting that having a science identity is relevant to A&P students and may be leveraged to support students in A&P contexts.