Background: An increasing number of educational institutions are incorporating virtual reality (VR) applications in the instruction methodology for their laboratory science courses. However, there is debate about the use of the physical vs. the virtual lab as according to research the former offers a positive research-training environment, whereas the latter offers safe and repeated practice in combination with an engaging experience. Purpose: This study explores whether virtualization applied to practically oriented education can: a) fulfill specific educational goals which correspond to the six levels of Bloom's Taxonomy, b) raise students' confidence about their knowledge and c) help students learn how to use an optical microscope in a physical biology lab. Sample: Fifteen graduates of the Athens University Department of Primary Education in Greece attending postgraduate studies in Science Education. Methods: The sample was separated into two cognitively balanced groups to be educated on microscopy by two educational methods: a) the traditional tutorial and demonstration method, and b) our proposed tutorial and simulation method with a VR biology lab, Onlabs. Participants completed both a Pre- and a Post-test to assess the acquired knowledge, and a worksheet to assess their ability to operate a real optical microscope. Results: Participants in the experimental group obtained higher Post-test scores and were better educated to correctly answer different types of questions corresponding to Bloom's Taxonomy than were members of the control group. Moreover, when working in the physical lab after having used Onlabs, the experimental group was more knowledgeable about the required experimentation skills compared to the control group. Conclusion: Our findings provided evidence in favor of using simulations. They pointed out that including simulations as a supplementary tool to the traditional face-to-face tutorials is a very promising prospective for grasping the details of laboratory knowledge, in a postgraduate program in Science Education.