Meeting Abstract

92.4  Sunday, Jan. 6  An exchange of countercurrents: Models, demos, and raps VOLTZOW, J.; Univ. of Scranton voltzowj2@scranton.edu

Many students learn better when they are actively involved in manipulations or other hands-on exercises. In content-rich courses like introductory biology, these exercises can be especially effective to help students make connections between seemingly diverse topics. Countercurrent exchange is a basic mechanism used by animals to enhance the diffusion of respiratory gases across their gills, to reduce heat lost to the environment through the surfaces of extremities, and to concentrate excretory products. This important concept arises several times over the semester in units on respiration, homeostasis, and excretion. I wanted students to appreciate that these functions depend upon the same underlying basic mechanism. Towards the end of the course, therefore, I ask students to build models or present demonstrations of countercurrents to the class. I give them a large amount of leeway, but they are required to do something that is three-dimensional or involves an activity. The assignment has resulted in games, skits, and even a rap video with thousands of hits on YouTube. The exercise helps students appreciate the shared principles that permit these multiple applications and gives them the opportunity to share their understanding with their peers. Most importantly, they have fun doing it and appear to remember it longer because they created something original using fundamental biological principles.