BIOLOGY 3P03 Lecture Notes - Lecture 2: Ion

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 3P03
• Professor: Wolfgang Kunze

Document Summary

As per convention - current is the movement of positive charge. So essentially, if chloride ions were moving out of the cell it would mean current is moving in (follows positive charge). Since iion = gion (em-eion), the sign of iion would be the same as that of driving force which is (em-eion); gion is always a positive value. If driving force/current is + : it means current is moving outward. If driving force/current is - : it means current is moving inward. Hence the current is moving outward (driving force is +). Therefore, sodium is moving out (current follows positive charge). We have now established that it is an outward current; since sodium (cation) is responsible for this flow of current, it is an outward current positive. Therefore, chloride is moving out (current follows positive charge).