By Gabe Kraljevic
Posted on 2019-09-20
How would a science teacher intertwine DNA and Mendelian genetics into lessons to younger audiences? Could elementary school teachers introduce this field by having different colored beads on a string to represent DNA and build on from there? How should teachers handle students making inappropriate comments such as “making the perfect human”?
— V ., North Carolina
I think DNA is at the heart of genetics and I don’t see a problem with teaching what DNA is and how it works in earlier grades. It is the method by which all complex living things transfer their traits to the next generation and it has its own language. Just building simple, single-strand DNA (I would use C, T, A, G alphabet beads) we can introduce codons and “read” traits encoded in the nucleic acid language. The complementary, non-coding strand can be introduced as the method by which the body is able to make accurate copies in a simple matching method. I’m sure that you’ll have students quickly making anti-parallel strands, reading codons, and determining which traits are coded on a strand.
We can physically show how cells are able to divide in mitosis and keep the genetic information intact within an individual. It is now a small step to meiosis and watching traits being separated into sex cells. Using beads on two different colors of string to denote chromosomes from two parents, students will discover why there are pairs of analogous chromosomes within cells. You can introduce dominant and recessive traits as analogous chromosomes are reunited during fertilization.
Issues in genetics, like eugenics or gender selection, can lead to powerful discussions in class—I don’t think they should be taboo.
Hope this helps!
Image by Zephyris via Wikimedia