Enter a clue or pattern or both:
The Clue
They act on impulses (8 letter answer)
The Answer
SYNAPSES
Tags
Notes
The answer SYNAPSES is so rare that it appears less than once every 2500 puzzles.
Definition
SYNAPSIS as a noun:
1. the side by side pairing of homologous maternal and paternal chromosomes at the start of meiosis