BSC 2010C Chapter Notes -Action Potential, Ion
Document Summary
Ions are atoms or molecules that have gained or lost one or more electrons, resulting in a net electrical charge. An atom that has lost one or more electrons becomes a positively charged ion, or cation, while an atom that has gained one or more electrons becomes a negatively charged ion, or anion. Ions are important in many biological processes, such as the transmission of nerve impulses, muscle contraction, and the maintenance of proper ph balance in body fluids. In addition, many biological molecules, such as proteins and nucleic acids, have ionizable groups that can contribute to their function. One example of an important ion in biology is the sodium ion (na+). Sodium ions are important for the transmission of nerve impulses, as they help to depolarize the cell membrane of nerve cells. When a nerve impulse is transmitted, sodium ions flow into the nerve cell, causing a temporary positive charge within the cell.
