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Pattern Matching | ||
| Issue | Naive Idea* | Scientific Idea |
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| Simplicity in Complexity | The detail of organic molecules is overwhelming, perhaps triggering a 'fear of chemistry' response, while the significance and power of the relatively simple patterns in organic molecules are lost. | Part of the wonder and elegance of biology derives from the observations that macromolecules are assembled from a few basic building blocks, that 100,000 or so DNA messages (genes) can be produced in humans with just four subunits (A,T,C,G), and that tens of thousands of proteins can be made with just 20 subunits (amino acids). |
| Dynamic Molecules | Organic molecules are fixed and static. | In living systems, organic molecules are often dynamic, changing shape, moving through the cell (or into and out of it), and entering into transformative reactions |
| Structure/Function | Structure and function are not closely related. | Small changes in structure can produce large changes in function, as in the two types of glycosidic bonds that allow assembly of sugars into either highly digestible starch or widely indigestible cellulose. |
| Bond Energy | In spite of the power associated with forest fires, house fires and burning of fuel, the energy associated with organic molecules is hard to comprehend. | Energy is captured in the bonds between atoms and released when those bonds are broken. Each transaction involves loss of some energy as heat. |
| Specific Bond Energy | Energy varies. | Each specific bond contains a known amount of energy. |
* A misconception or alternative idea has three primary features: it is a cognitive idea that differs in a significant way from the scientific idea, it is held by a sizable proportion of the population, and it is notably resistant to being taught away; it is often described as a conceptual primitive (Clement, 1982). There are many other types of errors in understanding besides misconceptions (Fisher & Lipson, 1986).
Clement, J. (1982). Students' preconceptions in introductory mechanics. American Journal of Physics, 50 (1), 66 - 71.
Fisher, K. M. & Lipson, J. I. (1986). Twenty questions about student errors. Journal of Research in Science Teaching, 23 (9), 783-803.
