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Abstract Energy is a crosscutting concept in science, but college students often perceive a mismatch between how their biology and chemistry courses discuss the topic. The challenge of reconciling these disciplinary differences can promote faulty reasoning—for example, biology students often develop the incorrect idea that breaking bonds is exothermic and releases energy. We hypothesize that one source of this perceived mismatch is that biology and chemistry textbooks use different visual representations of bond breaking and formation. We analyzed figures of ATP hydrolysis from 12 college‐level introductory biology textbooks and coded each figure for its representation of energy, bond formation, and bond breaking. For comparison, we analyzed figures from six college‐level introductory chemistry textbooks. We found that the majority (70%) of biology textbook figures presented ATP hydrolysis in the form “one reactant → multiple products” and “more bonds in reactants → fewer bonds in products”. In contrast, chemistry textbook figures of the form “one reactant → multiple products” and “more bonds → fewer bonds” were predominantly endothermic reactions, which directly contradicts the exothermic nature of ATP hydrolysis. We hypothesize that these visual inconsistencies may be a contributing factor to student struggles in constructing a coherent mental model of energy and bonding.
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This content will become publicly available on April 3, 2027
Making sense of ATP hydrolysis: how students reconcile conflicting ideas from chemistry and biology
Energy is a core concept across STEM, but disciplinary differences in how the topic is taught can lead students to develop a fragmented understanding. One well-documented misconception is that “breaking bonds releases energy,” a belief especially common when biology students reason about adenosine triphosphate (ATP) hydrolysis. Using Hammer’s resources framework, we investigated whether students’ misconceptions about exothermic bond breaking stemmed from a failure to activate chemistry knowledge in a biology context, or from a complete absence of that knowledge. We conducted semi-structured interviews in which introductory biology students first explained why ATP hydrolysis releases energy and then chose the reaction coordinate diagram that best represented the process. Initially, most students claimed that ATP hydrolysis releases energy because bonds are broken. However, when prompted with a reaction coordinate diagram, one third of students spontaneously corrected themselves, realizing that breaking bonds requires, rather than releases, energy. These results suggest that even when introductory biology students make errors in chemical reasoning, many actually possess the relevant underlying knowledge (e.g., “breaking bonds requires energy”) but fail to activate it in a biology context.
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- Award ID(s):
- 2244099
- PAR ID:
- 10679375
- Editor(s):
- Liao, Min-Ken
- Publisher / Repository:
- Journal of Microbiology and Biology Education Research
- Date Published:
- Journal Name:
- Journal of Microbiology & Biology Education
- ISSN:
- 1935-7877
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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