With two of the Sky Bet Championship's meanest defences taking on two of the meekest attacks a stalemate always looked on the cards.
That was until the 77th minute when Argentinian striker Ulloa pounced for his sixth goal in eight matches.
And eight minutes later Ward condemned Harry Redknapp's Rangers to a fourth defeat in six matches when he tapped in the second.
Up until then Rangers had created the better of the few chances which came about but were denied by Seagulls goalkeeper Tomasz Kuszczak while Brighton, themselves chasing a play-off spot, rarely threatened Rob Green.
The visitors created the first opportunity in the fifth minute when Will Keane and Armand Traore combined to set up Jermaine Jenas, who curled his shot wide from the edge of the area.
Kuszczak then saved comfortably from Traore but made a less convincing stop to keep out Junior Hoilett's deflected effort, grabbing it at the second attempt.
Both sides were playing with on-loan Manchester United youngsters in attack, with QPR's Keane facing his Old Trafford team-mate Jesse Lingard.
But it was one that got away from the Red Devils, Rangers' West Ham loanee Ravel Morrison, who came closest to opening the scoring in the first half.
The midfielder was likened to a young Paul Gascoigne by Birmingham boss Lee Clark following his two goals against them on Saturday, and he showed another glimpse of his talent after half an hour.
With one touch Morrison effortlessly spun away from his two midfield minders before striding across the pitch and unleashing a fierce, swerving drive which Kuszczak just managed to tip over the crossbar.
For Brighton, referee Robert Madley played a good advantage after Clint Hill fouled Will Buckley but Ulloa did not take it, planting his shot into the sidenetting.
And it looked like being the same story after the break with Kuszczak saving well from Hoilett at his near post and getting down low to keep out Traore's drive.
But 13 minutes from time Brighton's Spanish full-back Bruno made a rare foray forward and his low cross was turned into an open goal by Ulloa.
And Ward grabbed the killer second with another tap-in from Kazenga LuaLua's corner to complete another bad night for Rangers.