Having participated in teaching biology at a new place, I’ve completed a fresh run as an observer and found myself thinking a lot about introductory biology teaching decisions (the Bob Seger song “Against the Wind” has one of my favorite lines: “Deadlines and commitments/what to leave in… what to leave out.”). It occurred to me that there are two largely separable ways of teaching Introductory Biology that are quite different depending on what we want our students to be able to do. I believe the distinctions are not vastly unlike architects vs. engineers, or theoretical vs. applied physicists. It comes down to whether we want to be exposing our students to the how and why or the how-to and when-to. I’m almost exclusively in the former camp… but if we’re training medical students and technicians for industry, how much of ‘how does this work’ is needed? On the other hand, if we’re trying to attract and prepare P.I. (principal investigator)-level individuals and teach all comers ‘how life works’ alongside the wonders of what has evolved (and how), perhaps I can justify my approach. Continue reading
Both studies and common sense indicate that common threads running through our teaching provide students with reinforcement of both thread components and the things they connect. This approach also highlights conveying principles rather than fact collecting as our learning objective. The details of a basic ATP hydrolysis reaction illustrate both key principles (how enzymes actually implement their abstract aspects [speed up reaction; lower reaction barrier], roles for specific amino acids and protein folding), value of understanding chemistry in thinking about biology) as well as providing students with a tool that they’ll see over and over… and over again: the core mechanism is found in nucleotide addition, kinase and phosphatase reactions, pre-mRNA splicing, the timing mechanisms of GTPases [tubulin, EF-Tu, GPCRs], and… oh yeah: virtually every ATP-driven or -coupled reaction in the cell!
In my own little sphere, I’ve been fascinated by some of the contrasts between design and delivery of majors vs. non-majors biology courses. Non-majors courses are subjected to thoughtful cherry-picking: “What is most relevant to student lives or futures?”, “What has ties to society and their interests”, “What can we successfully convey in the allotted time?”. On the other hand, in teaching majors biology, I think there is a lot of pressure for the ‘kitchen sink through a fire hose’ approach: ‘everything’ must be force-fed to students at whatever pace necessary to get it ‘into their heads’, and there simply isn’t time for the extravagance of relevance or interest. I propose that teaching majors biology more along the lines of non-majors biology can make our students more interested and provide them with more knowledge and understanding when we’re done.
Lists of the ‘characteristics of life’ are a common element in introductory biology early lectures. Generally, these focus on movement, energy conversion, organization, etc.–all legitimate concepts. But the role of self-assembly in biology must not be underestimated; it’s a key feature of the flow of information in the Central Dogma (through the specific partnering of bases), folding of proteins from linear strings of amino acids (readily specified by linear structure of nucleic acids) gives rise to the functioning machines at the heart of almost all cellular work and action, and even membranes, while not members of the Central Dogma club, have function that relies critically on aspects of self-assembly. Without these properties, life would not only be impossible–they’re prerequisites for life to evolve from non-life.
Students store Introductory Biology topics in ‘bubbles’, often unrelated to each other or the world the students inhabit. One challenging area where this happens a lot is mutation–how mutations happen, why mutations have consequences, and even the idea that mutations happen to ‘us.’ One of my favorite articles from the popular press had a title similar to “Blue eyes arose through human ‘mutation’ thousands of years ago”, with the word mutation offset in quotes–to indicate blue eye changes aren’t real mutations? In trying to make the concept more concrete and interesting to students, I’ve accumulated a series of human phenotypes (and primary literature sources) that amuse students while also driving key concepts home. The role of mutation in generating diversity and driving evolution is quietly but steadily made as well.
Teaching the world of molecules to relative newcomers is challenging because it’s an invisible world with ‘rules’ that don’t always have a 1-to-1 correspondence with the macroscopic world (looking at you, hydrophobicity). A second issue is that while the molecules themselves are concrete things, we discuss them using their labels–A or adenine or glucose or ‘protein’. Too often, students end up with vague notions (or none at all) about these entities. Given that everything in the cell is made of and run by molecules, student success in thinking and understanding is critically dependent on what they’re picturing as molecules. I think care in and improvements of molecule display can go a long way towards making their lives easier and their understandings richer.