The transmission gate is pretty common in microprocessors. In NMOS circuits, it's a single transistor called a "pass transistor", but in CMOS it uses two transistors and is usually called a transmission gate.

It takes a logic signal as input, as well as a control signal. If the control signal is 1, the logic signal goes through to the output. If the control signal is 0, the transmission gate is disconnected. You can think of it like a relay-controlled switch, or a tri-state buffer.

The nice thing about MOS circuits is the gate resistance is almost infinite, so if you open a pass transistor, a gate on the output side will keep the old value (for a few milliseconds at least). So you can create latches almost for free. This is used very often in microprocessors. The disadvantage is the chip has a minimum clock speed, or else the data will leak away.

Pass transistors / transmission gates can also be used to implement multiplexers, selecting one of the inputs.

A disadvantage compared to regular logic gates is that a logic gate amplifies the input signal, while a pass transistor weakens the input signal. So you usually can't connect two pass transistor circuits together directly.

https://en.wikipedia.org/wiki/Pass_transistor_logic

Interesting, so it has different names in different contexts(NMOS vs CMOS.0 I'm familiar with the "pass transistor" nomenclature and have read about that in at least one of your previous posts. Good to know. Cheers.

Also not because of the bias voltages.