Inadequate academic functioning among students might be a main cause of the considerable dropout rates, and well-being and achievement problems in higher education. Few studies address the role of motivation for academic functioning. Thus, using Self-Determination Theory, the main goal of this study was to investigate motivational determinants of academic functioning among 406 biology students (mode age 21-25, 69.5% females) from nine higher education institutions in Norway. Data were collected using an online survey and analyzed using Structural Equation Modeling. Results show that teachers' autonomy-support positively predicts autonomous motivation and perceived competence among the students. In turn, autonomous motivation and competence positively predicts vitality, and negatively predicts dropout intentions. Achievement was only predicted by perceived competence. We recommend that instructors adopt an autonomy-supportive teaching style, for example by providing a meaningful rationale when introducing teaching and learning activities, for students to feel more competent and autonomous in their motivation.