How do you activate a particle system while holding a key and how to activate audio holding a key?

I am designing a space game with a friend and would like to know how would you about of making a script which makes it when i hold "z" (When the spaceship moves forward) audio plays and how do i make a particle system activate when i hold "z" as well - note i want the sound and particle system to stop on release of the key e.g. hold "z" engine sound effect plays and particle system on the engine starts then they both stop when i release "z" Thanks :D