Keith S. Taber
Energy can be made, but only in biology: Amy had learnt that respiration was converting glucose and oxygen into energy – but had learnt in physics that energy cannot be made
Amy was a participant in the Understanding Science Project. Amy was a Y10 (14-15 year old) student who had separate lessons in biology, chemistry and physics. When I spoke to her (see here), she had told me that respiration was "converting glucose into energy and either carbon dioxide and lactic acid, or just carbon dioxide". When I spoke to her again, some weeks later, Amy repeated that respiration was "converting oxygen and glucose into energy and carbon dioxide…it produces energy" ; that trees "need to produce energy and when they photosynthesise they produce like energy"and that food is "broken down and converted into energy".
Later in the same interview I asked her about her physics lessons, where she had been told that "there's like different types of energy" and that it "cannot be made or destroyed, only converted". Amy did not seen to have recognised any conflict between how she understood the role of energy in biology, and what she was taught in physics.
However, on further questioning, she seemed able to recast her biology knowledge to fit what she had been taught in physics:
So in physics, they tell you (that) you cannot make or destroy energy.
Yeah.
And in biology, they tell you that you can make energy from oxygen and glucose?
(No response – Pause of c.2 seconds)
But only in biology, not in physics?
Oh, erm, I suppose the energy, erm well in respiration, erm the energy must be converted from stored energy in food.
So in an interview context, once the linkage was explicitly pointed out, Amy seemed to recognise that the principle learnt in physics should be applied in biology. However, she did not spontaneously make this link, without which the nature of respiration was misunderstood (in terms of energy being created from matter). This would appear to be an example of a fragmentation learning impediment, as although Amy had learnt about the conservation of energy she did not immediately how this related to what she had studied in biology, about respiration.
