The team waived offensive tackle D.J. Jones to make room for Bynes on the 53-man roster.
Bynes, an undrafted rookie out of Auburn, spent one game on the Ravens' active roster earlier this season. He was with the Ravens in training camp, was released in their final roster cuts, and then signed to the practice squad on Nov. 9.
With both Jameel McClain and Brendon Ayanbadejo listed as questionable for tomorrow's game against the Texans, Bynes will provide depth at the inside linebacker spot.
Ayanbadejo (quad) is the more likely of the two injured linebackers to miss the game. McClain (MCL sprain) has said he intends to play.