Findings are presented from an ongoing study of three final-year, honors-level course units in the biosciences with a combined intake of 85 students. The data on which the analysis draws comprise semi-structured interviews with students together with findings from an Experiences of Teaching and Learning questionnaire. The investigation forms part of a wider project concerned with the enhancement of teaching-learning environments in undergraduate courses in contrasting subject areas. The findings presented in the paper focus on two interrelated aspects of the students' experiences within the teaching-learning environments represented by the three course settings. First, salient aspects of high-quality undergraduate-level learning are identified in the form of the students' evolving grasp of characteristic "ways of thinking and practicing in the subject". These ways of thinking and practicing in the biosciences were evident in the students' engagement with the research literature and with experimental data, and in their efforts to master the requirements and conventions of the subject for written and oral discourse. The second part of the analyses focuses on the teaching-learning environments represented by the three course settings. It was found that, despite taking markedly different forms in the three settings, the teaching-learning and assessment strategies pursued appeared to be broadly congruent with the promotion of ways of thinking and practicing in the subject. The quality of feedback to students also seemed pivotal, but needed to be understood in terms of the interplay of various factors, including opportunities for intrinsic as well as extrinsic feedback. Finally, the later years of undergraduate studies had called for a significant process of adjustment on the students' part to a step-change in study demands.