AAET Study Questions and Complete Solutions

What describes an atom in which the total number of electrons is not equal to the total number of protons, giving the atom a net positive or negative electrical charge Ion What is the negatively charged particle in an atom? Electron What has neutral particles, along with protons, and is found in the nucleus of an atom? Neutrons Which particles of an atom are positively charged? Protons What makes up the elements found in all matter? Atoms What is the voltage inside the nerve cell membrane in a resting membrane potential? -90 to -70mV What is the major ion outside a cell membrane? Sodium What is the major ion inside a cell membrane? Potassium What is the physiological term when depolarization occurs it causes a muscle and/or nerve fiber to either respond to a stimulus completely if it reaches threshold or no response if the depolarization is insufficient to reach threshold? All or non response What describes changing from a resting potential or polarized state to an excited state? Depolarization What causes the inside of the cell to be more positively charged relative to its resting state? Depolarization What describes when nerve cells are changed from an excited state back to a resting electrical potential or polarized state? Repolarization What causes the inside of the cell to be more negatively charged relative to its resting state? Hyperpolarization During the repolarization phase, sodium channels become inactivated and cannot be opened no matter how much depolarization occurs and no action potential can be generated no matter how strong the stimulus. What is this? Absolute refractory period