Changing colors and understanding: the use of mutant chromogenic protein and informational suppressor strains of Escherichia coli to explore the central dogma of molecular biology.

The central dogma of molecular biology is a key concept for undergraduate students in the life sciences as it describes the flow of information in living systems from gene-to-gene product. However, despite often being covered in many introductory life science courses, students may still have misconceptions surrounding the central dogma even as they move on to advanced courses. Active learning strategies such as laboratory activities can be useful in addressing such misconceptions. In the laboratory exercise presented here, senior undergraduate students explore the intricacies of nonsense suppressor mutations to challenge their understanding of the central dogma. The students introduce a plasmid carrying a nonfunctional chromogenic protein gene due to a nonsense mutation in a codon encoding the chromophore to various nonsense suppressor strains of Escherichia coli. Students then observe distinct chromogenic phenotypes, depending on the suppressor strain. Students showed a moderate increase in understanding of the central dogma. While the central dogma remains a challenging concept, active learning strategies like the one presented here can help reduce conceptual errors.

Teaching in the Time of COVID-19: Creation of a Digital Internship to Develop Scientific Thinking Skills and Create Science Literacy Exercises for Use in Remote Classrooms.

The extreme academic and social disruption caused by COVID-19 in the spring and summer of 2020 led to the loss of many student internships. We report here our creation of a novel internship for students majoring in the biological sciences. Student interns worked together to systematically categorize multiple episodes of This Week in Microbiology (TWiM). They annotated episodes by labeling relevant ASM fundamental curricular guidelines and the microbiology techniques described in several podcast episodes. Interns worked together, which advanced their written and oral communication skills while improving their scientific thinking skills. Faculty then enhanced each annotation by adding short figure-reading exercises that can be used in a variety of educational settings to teach science literacy. When surveyed, students reported greater confidence in analyzing and interpreting results from a variety of microbiological methods, improved communication of fundamental microbiology concepts in written and oral form, and enhanced ability to collaborate with others. Combined, this digital internship provided a unique opportunity for students to develop critical technical and scientific thinking skills and generated useful open education resources for teaching general microbiology in the form of annotated podcasts.

Just Figures: A Method to Introduce Students to Data Analysis One Figure at a Time.

Quantitative data analysis skills are basic competencies students in a STEM field should master. In this article, we describe a classroom activity using isolated figures from papers as a simple exercise to practice data analysis skills. We call this approach Just Figures. With this technique, instructors find figures from primary papers that address key concepts related to several of their course learning objectives. These figures are assigned as homework prior to class discussion. In class, instructors teach the lesson and include a 10- to 20-minute discussion of the figures assigned. Frequent and repeated discussion of paper figures during class increased students' confidence in reading and analyzing data. The Just Figures approach also increased student accuracy when interpreting data. After six weeks of Just Figures practice, students scored, on average, three points higher on a 20-point data analysis assessment instrument than they had done before the Just Figures exercises. In addition, a course in which students consistently practiced Just Figures performed just as well on the data analysis assessment instrument and on a class exam dedicated to paper reading compared with courses where students practiced reading three entire papers. The Just Figures method is easy to implement and can effectively improve student data analysis skills in microbiology classrooms.

Using Nonfiction Narratives in an English Course to Teach the Nature of Science and Its Importance to Communicating About Science.

The nature of science (NOS) is a foundational framework for understanding scientific ideas and concepts. This framework includes scientific methodology, the process of revising and interpreting data, and the ways in which science is a social endeavor. Nature of science literature treats science as a way of knowing that is based on observable phenomenon. While discipline-specific coursework teaches the factual information of science, it may fall short on teaching scientific literacy, a key component of which is understanding NOS. We have designed an English course that features nonfiction narratives describing the early days of epidemiology, hygiene awareness, and the current controversy surrounding vaccination. Using a validated assessment of student understanding of NOS, the Student Understanding of Science and Scientific Inquiry (SUSSI), we have determined that this science-themed English composition course was effective in teaching NOS. Student understanding of NOS increased between the beginning and the end of the course in eight of the nine parameters of NOS measured, with the greatest gains in understanding the role of revision and of creativity in science. Our data imply that the course helped students develop a slightly less naïve understanding of the nature of science and its importance in the development and dissemination of scientific ideas and concepts.

Development, Validation, and Application of the Microbiology Concept Inventory.

If we are to teach effectively, tools are needed to measure student learning. A widely used method for quickly measuring student understanding of core concepts in a discipline is the concept inventory (CI). Using the American Society for Microbiology Curriculum Guidelines (ASMCG) for microbiology, faculty from 11 academic institutions created and validated a new microbiology concept inventory (MCI). The MCI was developed in three phases. In phase one, learning outcomes and fundamental statements from the ASMCG were used to create T/F questions coupled with open responses. In phase two, the 743 responses to MCI 1.0 were examined to find the most common misconceptions, which were used to create distractors for multiple-choice questions. MCI 2.0 was then administered to 1,043 students. The responses of these students were used to create MCI 3.0, a 23-question CI that measures students' understanding of all 27 fundamental statements. MCI 3.0 was found to be reliable, with a Cronbach's alpha score of 0.705 and Ferguson's delta of 0.97. Test item analysis demonstrated good validity and discriminatory power as judged by item difficulty, item discrimination, and point-biserial correlation coefficient. Comparison of pre- and posttest scores showed that microbiology students at 10 institutions showed an increase in understanding of concepts after instruction, except for questions probing metabolism (average normalized learning gain was 0.15). The MCI will enable quantitative analysis of student learning gains in understanding microbiology, help to identify misconceptions, and point toward areas where efforts should be made to develop teaching approaches to overcome them.