Students are introduced to several key concepts of electronic circuits. They learn ...
Students are introduced to several key concepts of electronic circuits. They learn about some of the physics behind circuits, the key components in a circuit and their pervasiveness in our homes and everyday lives. Students learn about Ohm's Law and how it is used to analyze circuits.
It would be difficult to exaggerate the physiological significance of the transmembrane ...
It would be difficult to exaggerate the physiological significance of the transmembrane electrical potential difference, or ‘PD.’ This gradient of electrical energy that exists across the plasma membrane of every cell in the body influences nutrient transport into and out of cells, is a key driving force in the movement of salt (and therefore water) across cell membranes and between organ-based compartments, is an essential element in the signaling processes associated with coordinated movements of cells and organisms, and is ultimately the basis of all cognitive processes. The Nernst equation (named after its originator, the German Chemist and Nobel laureate, Walther Nernst), provides a quantitative measure of the equality that exists between chemical and electrical gradients and is the starting point for understanding the basis of the “membrane potential.” The Goldman-Hodgkin-Katz equation (named in honor of American David Goldman and the British Nobel laureates Sir Alan Hodgkin and Sir Bernard Katz; frequently simply referred to as “the Goldman equation”) calculates an estimated membrane potential that reflects the relative contributions of the chemical concentration gradients and relative membrane permeability for K+, Na+ and Cl-.