I’ll be posting sporadically this week because I’m teaching a brand-new series of study-skills workshops. (CCP people — look for flyers in the West Learning Lab, W3-26.) The first workshop is on how to use the textbook, and I thought I’d describe my favorite book trick: reading the book like you’re reading a mystery novel. (I learned this trick and many others from my colleagues, Jay Howard and Joan Monroe, in CCP’s Learning Lab.)
The trick starts with noting that modern science textbooks’ section and subsection headers are usually complete sentences. There’s a gen-bio book in front of me, and flipping to random pages gives me gems like Molecular clocks help assign dates to evolutionary events and The vascular cambium produces xylem and phloem in woody plants. Note that these are subsection headers — titles of parts of the book — not the paragraphs of the main text. You could probably get half the information of the book just by reading headers.
Here’s the trick: Read a header and ask two or three questions about it. If the header is Comnparing anatomical parts can reveal evolutionary relationships, your questions might be: Which parts? What do they reveal about evolutionary relationships? How do you do the comparison? How reliable? If the header is Organelles act to secrete substances, you might ask: Which organelles? What substances? What’s an organelle, anyway?
Flip through your textbook at random. Find headers and ask questions. Most of the time your question will be What is an X? That’s fine: much of biology is about naming and understanding objects and processes. As you gain experience learning biology, though, your questions will become more sophisticated. You’ll start asking things like: What are the monomers? How is that regulated? Are there developmental constraints? You’ll start to ask the kinds of questions that inspire entire research programs.
Anyway, when you open your textbook to study, read the headings and write down the questions. Then read the section with those questions in mind. Read the section with the goal of answering the questions. Don’t treat the textbook like a spy thriller, which you read to find out what happens. Read it like a murder mystery, which you read in order to solve the crime before the detective does.
When you read a mystery, you interact with the narrative in a more engaged way. You say to the detective, “Don’t trust that witness. He’s shifty!” Or, “Why aren’t you noticing the fact that the victim is just five feet tall?” You ask questions, you test assumptions, you give no character or description the benefit of the doubt.
Do the same thing with your textbook. And then, after you read each section, summarize it in the margins. Take notes on what you read.
Do these things, and I assure you that you’ll retain more information, that you’ll doze off less at the library, that you’ll do better on exams, and that you’ll be thinking more like a scientist.
Filed under: tips, video | Tags: conceptual superstructure, memorization, microbiology, narrative, structure and function, textbooks
This week the microbiology students are studying prokaryotic cell anatomy, so this is the week I spend a lot of time talking about Gram-positive and Gram-negative bacteria.
For the uninitiated, the nutshell description is that bacteria can be classified as Gram-positive (G+) and Gram-negative (G-) based on whether they retain a particular stain under the Gram staining process. Here’s a video. (I didn’t make it.)
Differential staining isn’t all that interesting in itself, but the anatomical differences underlying the differential staining behavior (and also underlying differences in pathogenicity and vulnerability to drugs) are. These anatomical differences come down to how thick is the peptidoglycan layer, whether there is a lipopolysaccharide layer, and stuff having to do with flagella. As always in comparative anything, they’re frequently laid out in tables (like this) and diagrams (like this) which appear in every microbio textbook there is.
Now, I do like textbooks, and I do like the figures and tables that summarize large amounts of information for quick reference. Where problems arise is in students’ tendency to zero in on them and spend all their energy memorizing them.
Scientists don’t memorize big lists of facts. Instead, they fit new facts into the knowledge they already have. In the case of G+/- bacteria, it comes down to what’s happening during staining.
When you add the first stain, the stain particles enter all bacteria. Then you add Gram’s iodine, which forms a complex with the stain particles. Then you wash the slide with alcohol, and the stain-iodine complex leaves some cells but not the others. The cells that retain the complex are G+, and the G- cells can be stained with something else.
That’s a narrative, and this business about particles entering cells, forming complexes, and then being too big to exit might remind you of other narratives. (Bananafish, anyone?) I know that my own brain takes better to stories than to lists, so I use this narrative to anchor all the facts I need to retain about bacterial cell-wall anatomy.
Like this: Is it G+ or G- that has the thicker peptidoglycan layer? Well, it’s the G+ that retains the first dye, so it’s the G+ whose cell wall is impermeable to the stain-iodine complex. It therefore seems that the G+ must have the thicker peptidoglycan layer. Here’s another: Which has the lipopolysaccharide layer? It turns out that the alcohol wash disrupts the LPS layer, and that disruption promotes permeability to the complex. So it’s the G- that has it.
Learning biology means learning a lot of facts, but it can help to connect them together. Form conceptual complexes. In this case, I grouped some facts about structure to some facts about function, and I used the narrative of the staining procedure to give me a handle on it all. Grouping facts into complexes reduces the sheer number of things you have to remember — and more important, it’s understanding rather than simply remembering.
Filed under: tips | Tags: aliens, biochemistry, fear, narrative, textbooks
College biology textbooks often start with chemistry, so before even touching on cells or leaves or intestines, beginning general-bio students are faced with (roughly in this order): elements, atoms, subatomic particles, ions and isotopes, atomic orbitals, electron energy shells and the octet rule, covalent and ionic bonds, electronegativity, molecular polarity and its consequences for the properties of water, carbohydrates, lipids, proteins, and nucleic acids. All this in one chapter! It’s been hitting our beginning gen-bio students like water from a firehose, and the last couple weeks I’ve been seeing a lot of students who feel lost, intimidated, even freaked out.
What’s with the initial conceptual onslaught? One theory hypothesis, which I call the Intimidation Hypothesis of Biological Pedagogy, rests on the notion that many undergraduate biology programs want to see some sizable fraction of its students disappear before the registrar’s drop deadline. The hypothesis goes on to suggest that publishers accommodate these programs by front-loading their textbooks. I personally find this hypothesis plausible but untestable — and and not particularly helpful for students.
More useful is the Hypothesis That Science Isn’t Fiction. Imagine that instead of opening your hundred-dollar bio textbook, you’re opening a nine-dollar novel. The first chapter is typically easy-going: you meet some of the characters, you take a tour of the town or apartment building or starship, you get a general idea of what life is like before the main character gets dumped or the murder victim is found or whatever. In subsequent chapters things get complicated, but it’s all basically human stuff: people talk, fall in love, fight, murder each other, cook meals and blog about them, clone themselves and overthrow governments.
Now imagine the same novel, only now it’s written for space aliens. And not aliens like Cardassians (that is, grumpy human beings + forehead ridges) — I’m talking about aliens who are made of gas, who are the size of large asteroids, and who live in the majestic isolation of comets on millennium-scale orbits. An easy-going first chapter would no longer be adequate, because in order for the rest of the novel to make sense, there would be much more information that wold have to be conveyed. Information like what human beings are, what emotions do human beings experience, and how are they expressed. Like what is money, what are jobs, what is food, what’s a promotion, what’s a boss, what is murder, what’s a cop. Like what is a relationship, what is communication, what is the self. The book would have to start with basic definitions of the actors, how they interact, and what meanings those interactions have.
That’s what’s going on in that textbook. The characters in the bio text are not human beings, but molecules, gradients, tissues, biogeochemical processes, etc. The interactions are things like chemical bonds, catalysis of reactions, acid-base reactions, redox. It’s important stuff to understand, and we happen not to understand it already because we’re asteroid-sized gas-blimps peering through microscopes.
The good news is that the stuff in later chapters is different. Not necessarily easier, but probably not so alien-seeming.
