Where is the signal blocked?

In a Bi-Wire setup, where are the low frequency signals blocked on the cable going to the mid/tweeter? Are the signals stopped at the crossover in the speaker, or do they never travel down that cable from the amp? I suppose the opposite about the higher signal can be asked as well, having any effect on the low signal cable.

All frequencies travel down both runs of a biwire cable to the speaker. Low frequencies are not feed to the mid/tweeter due to the crossover as in single wire.

Some equipment has built-in band-pass filters in the receiver/control unit.
Usually, the speaker's crossover will reject the frequencies not needed by the given driver(s) (passive bi-wiring).