The three things I learned in college:1) I am [expletive]2) Everyone else is [expletive]3) Mitochondria is the powerhouse of the cell
Overview: Labels vs. the things they label
I’ve written elsewhere about challenges inherent in any field with specialized vocabulary. In this post, I’d like to put forward some ideas for delivering biology with meaning… by literally talking different (to paraphrase the Apple ad) and requiring students to do so. Foreshadowing: this will be a post of quotes. For an overview, I’ll turn to the Bard, who commented on the outcome when we allow students to merely recite sounds and buzzwords in their answers:
It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.”–Shakespeare, Macbeth
Sounds vs. meaning–what to do?
My overall goal is to present ideas in ways that require students to chew on and digest words–to pause and consider meaning rather than collecting word- or even sound-streams. Similarly, when seeking products from students or measuring their understanding, I think we have to prevent them from reciting memorized snippets and push them to transform on phrasing or example into another.
Talk Different: colorful language as communication
The thing that astonished him was that cats should have two holes cut in their coat exactly at the place where their eyes are.
—Georg Christoph Lichtenberg
I think the key to ensuring that we are teaching biology with meaning is a combination of choosing our own words to render them noteworthy and constraining our students to synthesize during their assembly of meaning. One way I attempt to achieve this is by purposefully using unexpected, uncommon, or ‘off beat’ images or verbal constructions when presenting ideas. I’m hoping to make folks stop and think “why does he think that phrase fits?” or “can that be a description of the thing I’ve always heard of as ________” or “how can you say that about DNA” (or even “what is he talking about”). Consider: what do you think the average student visualizes when the phrase “information molecule of the cell” passes by in lecture… anything? Other than “I should memorize that phrase for the exam”? I think we can do better with “These structures [a string of nucleotides] that I’m projecting on the screen are instructions for everything that happens in your cells…”
“…the instructions for making a peacock’s tail look like:”
Reason different: teaching by analogy
This is really a topic for a whole other blog post, so I’ll leave just a snippet here. The Big Idea is akin to the one behind the VocabuWary tool I created (coming soon in a plug-in free, plays anywhere version!)–if a student has only one way of looking at or thinking about and talking about a process, how can we claim that they understand it? Any discussion of transfer involves movement to another medium or domain. Further, many (most?) great scientific thinkers have done some of their biggest thinking analogically–think Einstein riding on a photon, Darwin comparing Nature-al selection to the selection performed by farmers and pigeon breeders… and likely the way you present any complex conceptual framework to new learners… it’s a means of providing (or identifying) the scaffold onto which they can construct meaning.
Examine different: Assessments as big blind spots
[For example, we will explain]…why the turtle goes to the sea after laying its eggs by saying that’s an ‘instinct’…. that’s just a name that feels explanatorily soothing to us… we very often feel like we’ve explained something when we’ve just uttered a magic word to make the puzzle feel like it goes away.
—Prof. Jeffrey Kasser
- List the steps in meiosis => List the names of the steps of meiosis (student with ONLY the labels gets 100% vs. student understanding process but momentarily blanking on their Greek fails)
- What different machines participate in transcription vs. translation? => What are the names of the machines… (students having memorized the symbolic representations => 100%; students understanding about matching of groups of threes to ‘specify’ amino acids, the similarities and differences between joining bases and amino acids fails)
- What are the critical components of DNA replication => What are the names of the machines involved in DNA replication (do we care what they are labeled, or do we care what they do?).
- One of my favorites for decades has been questions requiring elucidation of DNA Pol’s enzymatic activities: “DNA polymerase has a 5′ to 3′ DNA-dependent DNA polymerase activity, and a 3′ to 5′ proofreading exonuclease, a 5′ to 3′ exonuclease activity. I’ve gotten this litany from students who have no idea what a ‘five prime’ is, or even which molecule it’s associated with.
Listen different: no jargon allowed
“If you can’t explain it simply, you don’t understand it well enough.”
Deliver different: Some concrete examples
“See that bird?” [my father] says. “It’s a Spencer’s warbler.” (I knew he didn’t know the real name.) “Well, in Italian, it’s a Chutto Lapittida. In Portuguese, it’s a Bom da Peida. In Chinese it’s a Chung-long-tah, and in Japanese, it’s a Katano Tekeda . You can know the name of that bird in all the languages of the world, but when you’re finished, you’ll know absolutely nothing about the bird. You’ll only know about humans in different places, and what they call the bird. So let’s look at the bird and see what it’s doing–that’s what counts.” (I learned very early the difference between knowing the name of something and knowing something.)
—Richard Feynman, What do you care what other people think?
One of the hardest things to to is to teach students things they already ‘know’–to get beyond their lovely trees and consider the awesome forest they represent. Frankly, it’s much easier to memorize details and names than it is to grasp concepts, purpose, and mechanism. This is one of the goals of thinkBio’s InfoFlow: Protein (credit here also goes to many folks who’ve given feedback and inspiration) software exploration. While everybody ‘knows’ biology’s Central Dogma, most disastrously stated as “DNA makes RNA makes Protein” or trivialized as “DNA <=> RNA => Protein”, there are a lot of deep ideas embedded in there; again there is a tension between delivering biology with meaning and tossing trivialities to the sharks. Consider:
- Why are bases shaped like bases, but amino acids shaped so diversely?
- Is there a reason that the bases are like peas in a pod, but amino acids run the gamut of shapes, flexibilities and ‘feels’?
- Why do each have common elements (backbone) and unique elements (sidechains) [dealt with separately here]
- Could Mars life’s Central Dogma sequence be Protein => RNA => DNA ?
- Is the only reason DNA ‘comes before’ RNA because they’re alphabetical?
Not all of these are addressed in the InfoFlow simulation, but many of the broad concepts are, partly by packaging all of it in an analogy to an heirloom book of recipes (precious DNA copy, all of which is duplicated for a son or daughter), a quick copy of one page (hand-written note used for a single recipe to be made that day), and the wholly transformed version (a sandwich made from the instructions found in the book). The goal here is to give new learners a conceptual framework on which to hang the myriad details-of-implementation found in cells, and to pull advanced students out of the details and up to a higher-order examination of Big Ideas.