KINE 1P90 Lecture Notes - Lecture 5: Cell Membrane, Fluid Compartments, Membrane Potential

• School: Brock University
• Department: Physical Education and Kinesiology
• Course: KINE 1P90
• Professor: Klentrou Panagiota

Document Summary

For a muscle to contract, it needs a neural impulse. Neural impulses are electrical currents that pass along nerve fibres. Myelin insulates the axon and allows for faster nerve conduction. In other words, the electrical charge inside the cell is different than the electrical charge outside the cell (electrically polarized) This is caused by a difference in the relative number of cations (+) and anions (-) in the intracellular fluid (icf) and the extracellular fluid (ecf) The ions responsible for producing membrane potential: sodium (na+, potassium (k+, anions (a-) large intracellular proteins. Excitable cells (nerves and muscle) have the ability to produce rapid, transient changes in their membrane potential. These brief changes serve as electrical signals. The membrane potential in a nerve cell is -70mv. The inside of the cell (icf) is -70mv compared to the outside of the cell (ecf) Depolarization the membrane becomes less polarized compared to the resting potential.