Abstract
Temperature is one of the most important elements of an animal’s world, and living things cannot avoid dealing with the thermal environment. The temperature sets the characteristic scale of microscopic motions, as well as the intrinsic rates of biological processes, with consequences for every level of physiological organization. In this thesis, I present research highlighting three contexts in which thermal considerations constrain the design of excitable cells. In the first study, I describe how an unusual potassium conductance protects Caenorhabditis elegans pharyngeal muscle from thermal noise. In the second study, I present results that suggest a role for changes in the spatial distribution of conductances in thermal acclimation of the stomatogastric ganglion of Homarus americanus. Finally, I describe a model of an ultrasensitive thermosensitive cell, which shows that ultrasensitive behavior can arise from the competitive action of a kinase and a phosphatase.