Features of measured and modeled Ig in the presence of extracellular Cd²⁺. (A) Maximal Ig_ON-V_t relationship. (B) Maximal Ig_OFF-V_t relationship. Time constants–V_t relationships for Ig_ON (C) and Ig_OFF (D). Relationship of exponential fit coefficients to V_t for Ig_ON (E) and Ig_OFF (F).