I was watching the Directors Cut of Alien, which I haven't watched very much, and noticed for the first time that it got changed after Dallas' death. After Ash exits from the galley, Ripley looks at Lambert and she has a bit of snot running out her nose, then it cuts back to Ripley and she gets up from her seat. Then it cuts to her entering Mother.
In the original cut it goes Ash exits, Ripley looks at Lambert, Lambert looks at Ripley, then cuts to Action Parker (TM) going to refuel the flamethrower. That Parker scene got cut from the DC.