Penn (22-7) closed one of the most successful seasons in the program's history, highlighted by a third Ivy League title.
Senior Alyssa Baron scored 17 of her 25 points before intermission for the Quakers, who built a 32-17 lead before the Longhorns began slicing the deficit. Texas trailed by 38-31 at the break.
"We were feeling good, we were feeling it, but sometimes leads just go away," said senior Courtney Wilson, who scored 10 points. "Basketball is a game of runs."
"In the second half, they ran the ball at us and we didn't get as set on the defensive end, which was our goal," McLaughlin said.
Penn freshman Sydney Stipanovich saw just 19 minutes of action because of foul trouble but scored 14 points.
Imani McGee-Stafford, a 6-foot-7 sophomore center, finished with 20 points and 12 rebounds for Texas.
"I thought she was great," McLaughlin said. "She's not only 6-foot-7, but she is incredibly mobile. She's a factor because she changes the complexion of the game around her and around the rim. To her credit, she made some really difficult shots at key parts of the game."
Nekia Jones had 14 points and Empress Davenport scored 10 for the Longhorns.
The loss meant the end of the road for Baron.
"We were able to keep improving year to year," she said of the Quakers' program. "I think we are leaving the program in good hands and I see continued success in the future."