Nicole Ari Parker, Tichina Arnold and Tracee Ellis Ross at the BET conference. (Erin Williams/The Washington Post)

After 50 years in show business, you know how to steal a show.

The grande dame sat quietly in the audience of the panel discussion as actresses two generations her junior vented about their ups and downs in the industry. But they knew she was there, and that it was time to salute her.

“I want to hear from Cicely Tyson,” said Tichina Arnold, one of the younger stars on the dais, and the room turned its gaze to the 77-year-old Emmy winner, one of many high-powered guests at BET’s “Leading Women Defined” summit at the Four Seasons on Wednesday.

Tyson demurred, shaking her head to say no.

And then — just as the organizer who had been advancing towards Tyson with a microphone started to turn away. . . well, maybe on second thought, she did have a thing or two to say, reports our colleague Erin Williams.

Tyson took the mic and told an indignant story about how, after everything she’s done in her career, she was recently asked to do a screen test to prove her talent — and then she still didn’t get the job.

But then, “it’s not what people do to you, it’s what you let them do to you,” Tyson said. “You have your own power and you have to execute it.”

Gotta end it on a positive note, after all, for a panel called “Black Girls Rock: Positively!” The BET confab tapped a quartet of actresses lauded for “authentically” and “honorably” portraying African-American women.

So how it is these days, in the biz? Nicole Ari Parker groaned about typecasting — “It’s weird in 2011 that somebody can say ‘We’re not going black’” — and bashed the new cartoon “Mars Needs Moms” for its stereotypical dreads-wearing bad guys. (On a more superficial note — yes, ladies, Parker’s dreamy husband Boris Kodjoe was in the audience.)

But Tracee Ellis Ross, formerly of the sitcom “Girlfriends” noted that no one these days can coast on their resume. “My mother still has to prove herself, but her identity is not wrapped up in it.” (A worried flack later called to let us know that Diana Ross’s daughter does not officially speak for the singer.)

But Arnold, best known as the mom on “Everybody Hates Chris,” insisted things are getting better, with more roles open to all ethnicities. And C.C.H. Pounder — the Na’vi healer from “Avatar” — told the room she doesn’t care if a role wasn’t written for her demographic: “I never read the ethnicity,” she pronounced. “ I read the play.”