PSY 1101 Lecture Notes - Lecture 3: Axon Hillock, Myelin, Axon Terminal

• School: University of Ottawa
• Department: Psychology
• Course: PSY 1101
• Professor: Gary Capstick

Document Summary

Some things can pass through, while others can not. Relatively impermeable to sodium (na+) and potassium (k+) at rest: na+ in higher concentration outside the cell, k+ in higher concentration inside the cell, chemical or concentration gradient. Overall, inside of the cell is negatively charged, compared to the outside of the cell. A brief electrical charge that travels down the axon. Electrical signal transmitted along the axon by the diffusion of charged atoms. The membrane becomes permeable to sodium (na+) and. Series of channel openings along the axon that allows the diffusion. Sodium channels open at the axon hillock (at the very beginning of the axon) Since sodium is positively charged, the inside becomes positive. Resting membrane potential is then restored: depolarization. Potassium channels open and potassium rushes out of the cell, making the cell negative on the inside again. Sodium pumped back out, while potassium pumped back in. Refractory period: a period in which the neuron can not fire.