ANP 1106 Lecture Notes - Lecture 7: Nicotinic Acetylcholine Receptor, Histamine, Vesicle Fusion

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1106
• Professor: Joanne Savory

Document Summary

In the cells of the body ions are unevenly distributed. This uneven distribution creates a charge separation the results in voltage: voltage is known as a potential. Biological potentials have voltages ranging from -90 to -70 mv but can briefly jump to +55 mv. Flow of charge as a result of potential is current: the amount of current that will flow depends on the resistance, the membrane polarization provides the electrical gradient that drives ion. Insulators have large resistance, conductors have low resistance movement across the membranes of excitable cells. Movement of ions creates electrical charges: can be caused by concentration or voltage gradients, voltage gradient: difference in charge between two regions that allows a flow of current if the two regions are connected. The ions are unevenly distributed: extracellular space: lots of na+ (140 mm), cl-, small amounts of k+ (5 mm) Intracellular space: lots of k+ (140 mm), negatively charged proteins, small amounts of na+ (15 mm)