Integrated response, variance due to transmitted noise and SNR in the full pathway model when varying ambient concentration and receptor complex size. (A) Integrated response of the motor. (B) Variance of the motor including only contributions from receptor switching, ligand diffusion, methylation and phosphorylation. (C) Individual contributions to the variance of the motor. (D) SNR based on the signal response and variance shown in (A) and (B). (E) SNR as a function of receptor complex size at ambient concentration 0.02 (solid), 0.03 (dashed) and 0.05 mM (dotted line). Optimal complex size is indicated by arrows.