To determine the length constant, or space constant, you can inject current (without activating an action potential) and plot (Vr is the resting membrane potential; electrotonus is the steady-state voltage) A) Ln (V - V_r) vs x during conditions of electrotonus B) Ln (V - V_r) vs t during conditions of electrotonus C) Ln (V - V_r) vs t during the rise phase or decline phase of electrotonus D) Ln (V - V_r) vs t only during the decline phase of electrotonus E) Ln (V - V_r) vs t only during the rise phase of electrotonus

Question

Quizplus · Accepted Answer

The length constant, or space constant, is determined by measuring how the voltage changes with distance (x) along a neuron during steady-state conditions (electrotonus), not with time (t). Therefore, plotting Ln(V - Vrest) vs x during conditions of electrotonus is the correct method.

To Determine the Length Constant, or Space Constant, You Can