2020 Volume 61 Issue 1 Pages 167-173
The biology curriculum for upper secondary school students now introduces several concepts of molecular biology. This has been accompanied by an increased need for more teaching materials. For example, restriction enzymes are generally described in all authorized upper secondary school biology textbooks. However, the experimental method is time consuming, and available time in class is limited. Therefore, we developed a new teaching material and method in which experiments involving restriction enzymes can be performed by students within a single 50-minute class. Since the experiment was to be conducted within one class, a DNA fragment containing one restriction site was prepared, and the reaction conditions were optimized to shorten the duration of the experiment. DNA 1.0 μL, the restriction enzyme 1.0 μL, and buffer 1.0 μL were mixed, sterile distilled water was added to make the total volume 5.0 μL, and the mixture was allowed to react for 20 minutes at 37°C. Electrophoresis was then performed at 100 V for 15 minutes using a 2.0% agarose gel. To help students understand that restriction enzymes identify and cut specific DNA nucleotide sequences, the learning plan was designed so that the students would be required to think about the size of the DNA fragments. After the lesson, 85% of the students recognized that the size of the band obtained after electrophoresis was related to the distance between the recognition regions of the restriction enzyme, demonstrating the effectiveness of the new teaching material and method.
