Drawing out the structure of DNA

Anveshna Srivastava

“He who would learn to fly one day must first learn to stand and walk and run and climb and dance; one cannot fly into flying” – Friedrich Nietzsche

Learning is a progressive endeavour, where systematicity plays a significant role. One cannot write without knowing the alphabet! The order may not be rigid every time, but a systematic progression from simple to complex conceptual understanding helps the learner to see things in perspective, rather than be lost in the conundrum of conceptual network. Still, each learner is a unique individual with unique learning processes (von Glasersfeld, 2001), and it makes it difficult for the facilitators to use their discretion in using representational notations which can map on to the receptive structures of all learners.

multiple-reps This mapping difficulty can be alleviated to a large extent through the use of different representations which coheres with the conceptual story narrated by the facilitator. In our day to day learning interactions, texts and diagrams form the most widely used representational notations. The diagrams used are visually more appealing than the text but not so much that the learners can connect textual information with them. One of the solutions to this problem is to use multiple external representations which can help learners to complement information and processes, constrain multiple interpretations and construct deeper understanding (Ainsworth, 1999). But, a mere inclusion of more number of representations will bombard learners with too much of information, and hence it is important that learners engage with different representations used. This is possible if there is a logical progression to the introduction of these representations.

In this article, I will introduce a few representations which are simple enough to construct and which if exploited in a certain sequence can aid in the sense-making of a complex biology concept, the structure of the DNA.

The context
The Deoxyribonucleic acid (DNA) molecule has a special place amongst homo sapiens, who are probably the only species on the planet whose quest for knowledge has led to the extensive exploitation of this carrier of the units of heredity (read ‘genes’). DNA’s biological significance of being a carrier of genes has hugely contributed to not just our understanding of other biological organisms but also to the advancement of medical sciences, where humans have tremendously increased their average life span. Since the discovery of DNA’s structure in 1953 by Watson and Crick, learning fields like ‘molecular biology’, ‘biotechnology’, ‘bioengineering’, etc., have emerged to specifically tap into the various possibilities offered by this molecule.

The author is a research scholar at Homi Bhabha Centre for Science Education, TIFR. Her research interest includes exploring students’ understanding about the DNA structure. She can be reached at anveshna@hbcse.tifr.res.in.

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