Neruo Lab BIG Quiz #1 [LAB 3&4]

Membrane/transmembrane potentialpotential/voltage difference between the inside and outside of the neuronal membrane

Restingsynapticreceptoraction

Concentrationselectrical gradientsopening and closing and particular ion channels

Measures voltage along the outside of cell"reflection" of inside of cell*THIS IS WHAT WE USED*

Measures voltage difference between inside and outside of cell membraneinsert one electrode into cell, penetrating the cell membrane without compromising neuronal health

Measures electrical currents through single ion channelsisolating a patch of membrane with only 1 or 2 ion channelsmeasure ion flow

Direct visualization of voltage difference across the cell membrane--> spatial and temporal resolution of membrane potential- need voltage sensitive dyes- evaluation with microscopy

Standard prep for study of AP before squid giant axon was usedlargest and longest nerve in most vertebrates
carries info to and from spinal cord(origin)- extends along almost entire hind limb

Composed of many neurons

Carries motor signals to muscles
sensory signals from muscles and skin

Common shape for Action potentals
TWO parts
rapid and brief depolarization conducted DOWN length of axon to convey info from one place to another

Signal results from pattern of opening and closing of voltage gated Na⁺ and K⁺ channels

Extracellular recording of sum of multiple single APs firing at the same time
helps understand neural conduction

- do NOT see - Large (+) depolarization of single AP- DO see - large traveling wave of negativity
- in each individual Axon = AP = rush of inward Na+ flow --> external loss of (+) charge=> increase in negativity <-- this is what we end up measuring

1. A=0, B=0 --> A-B=02. A=-1, B=0 --> A-B=-13. A=-1, B=-1 --> A-B=04. A=0, B=-1 --> A-B = +15. A=0, B=0 --> A-B=0