When cells communicate by the signaling process, one cell produces a that must be received by the on or in the responding cell.

a. signaling particle; signal enzyme
b. signaling molecule; signal receptor
c. hydrophilic signal; hydrophilic receptor
d. cell division signal; plasma membrane
e. nonpolar signal; nonpolar receptor

The correct answer is option B.

Explanation:

When the cells interact through a signaling process, one cell generates a signaling molecule. The signaling molecules refer to the molecules, which are accountable for conducting information between the cells in the body. This signaling molecule must be attained by the signaling receptor present on or in the responding cell.  

A signaling molecule needs to combine with its receptor to start a reaction. The receptors are proteins, which combine with their signaling molecules either internally or externally within the cytoplasm or nucleus. This phenomenon is termed as signal transduction.  

enzyme speed up the reactions