BIOL 1412 Lecture Notes - Lecture 3: Resting Potential, Axon Hillock, Threshold Potential

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1412
• Professor: Jennifer Mcleese

Document Summary

Topic iii: nervous system i neurons, impulse generation & transmission: neurons review, electrical properties of cells: When stimulated (usually on cell body or dendrites) an electrical impulse may be generated and propagated along the axon = nerve impulse: ionic concentration differences across the cell membrane (gradients) Large, negatively charged organic ions (org-) are non-diffusible proteins: important ions: Always open: permeability of cell membrane to ions. Determined by ion channels - ions diffuse through them down conc. gradient. These channels (especially k+ - more numerous) are: gated. More k+ than na+ in a neuron cell membrane more important in establishing the resting membrane potential (rmp) Open in response to stimuli: e. g. permeable to k+ at rest (no stimulus) 2: membrane voltage changes = voltage gates, chemical e. g. binding of hormone or, temperature = thermal gates, mechanical deformation = mechanical gates neurotransmitter (nt) = chemical gates, neuronal physiology, resting membrane potential (rmp): cell membrane = membrane potential.