NEUROSCI 101 Lecture Notes - Lecture 7: Reuptake, Metabolite, Vagus Nerve

• School: Duke University
• Department: Neuroscience
• Course: NEUROSCI 101
• Professor: Christina Williams

Document Summary

Test i questions: applications, mc, t/f, free response. **review graded potential vs action potential** (what are each, what causes each, what are the mechanisms, where are the ions, etc. ) Lack of voltage-gated ion channels in dendrites, particularly na+/k+ channels. Graded potentials (epsp and ipsp) travel from the dendrites and are summed up : epsp: reach the threshold fire action potential na+ rushes in. False in giant squid axons, action potentials are faster than graded potentials. Graded potentials are always faster: action potential requires opening/closing/opening/closing and so on takes time. A +3mv charge is administered to a giant squid axon. Voltage reading would decrement as it moves away from the site of stimulation: does not remain the same strength, depolarizes (becomes more + inside axon) rather than hyperpolarizing (more -) Graded potential because it has not reached threshold. Action potentials do not decrement (all or none) Myelinated is faster than unmyelinated but both are slower than graded potential occur in axon.