BODY WEIGHT, CELL SURFACE, AND METABOLIC RATE IN ANURAN AMPHIBIA

Abstract

Rate of whole animal oxygen consumption and muscle cell surface concentration were measured as a function of body weight in 6 species of frogs ranging in adult weight from 1 g (Pseudocris nigrita) to 350 g (Rana catesbeiana). Both metabolic rate and surface concentra-tion varied directly as body weight (W)-^- for each species. Buccopharyngeal frequency was a species constant in the Rana species. Assuming a central nervous stimulation of a surface dependent muscle respiratory system, a simultaneous treatment of neural activity and muscle surface was suggested as a mechanism for the control of in vivo respiration rate. Findings of other authors on tissue metabolic rates as a function of species and temperature also suggested a two-factor system. Changes in cell surface concentration and metabolic rate changes during ontogeny were correlated in the frog and other vertebrates.