9/28 Neuroscience Lecture Vocabulary: Neuronal Information & Membrane Dynamics 9/28

Vocabulary flashcards focusing on electrophysiology, membrane permeability, diffusion, and equilibrium concepts discussed in the lecture.

Voltmeter

A device that measures the difference in electrical charge between two locations relative to a designated ground.

Ground

The baseline location in electrical measurement that is automatically defined as equal to zero.

Diffusion

The movement of particles from an area of high concentration to an area of lower concentration without requiring energy.

Concentration Gradient

A difference in the concentration of a molecule between two locations, which creates and drives movement across space or a membrane.

Impermeable Membrane

A membrane or barrier that does not allow a specific molecule or substance to cross through it.

Semi-Permeable Membrane

A membrane that selectively allows certain substances to cross while blocking others, or permits substances to cross at different rates.

Equilibrium

The state in a system where the rate of flow in is equal and opposite to the rate of flow out ($\text{flow in} = \text{flow out}$).

Electrical Gradient

A gradient produced by differences in charge where opposite charges attract and like charges repel, driving charged ions across space or membranes.

Hodgkin and Huxley

Researchers from the 1940s and 1950s who won a Nobel Prize for work on neurons and established the convention of placing the electrical ground on the outside of the cell.

Resting Potential Target ($-70\,mV$)

The key voltage value ($-70\,mV$) where the inside of a neuron is less positive (more negative) than the outside.