Practice question

Patch-clamp achieves electrical isolation of a tiny membrane patch by forming a gigaohm seal between a fire-polished glass micropipette and cell surface, enabling resolution of picoampere currents through one ion channel. Developed by Erwin Neher and Bert Sakmann, configurations include cell-attached, inside-out, outside-out and whole-cell, allowing study of voltage-gated, ligand-gated and mechanosensitive channels, single-channel conductance, open probability and kinetics. Single-unit recording monitors whole neuron firing, EEG sums thousands of cortical postsynaptic potentials, MRI uses proton resonance for anatomy, none resolve individual channel activity.