Outlined in this publication is a basic laboratory exercise which characterizes tubular secretion, using an isolated renal tubule preparation from teleost fish. Background information is given showing how these tubules of teleost fish, particularly marine teleosts, correspond to the proximal tubule of mammalian kidney. Materials needed, including a number of species suitable for the exercise, equipment, and medium are described. A second item of interest is a description of a system developed for the purpose of organizing instruction and evaluation of student performance in an integrated multidisciplinary educational program for medical students. Instructional objectives, with related questions, are given. Two articles on methods for anesthetization of lower animals (snakes and insects) are included and references cited. Other items of interest include book reviews, letters to the editor, and an extensive review of audiovisual materials. (EB)