She continued, "These are issues that are important to highlight, that there is an imbalance and that gender bias does exist, and we all need to stand together to support one another and highlight that imbalance -- continue to fight for our rights. I think it's important to just -- as a woman, as a feminist, as a mother and as a member of society -- it was important to me to be there."
Johansson also opened up about her new film, the big-budget blockbuster "Ghost in the Shell," in which she plays a cyborg commander hunting down cyber criminals.
"I think part of the appeal [of 'Ghost in the Shell'] was knowing that the opportunity to be kind of the front and center of a big franchise vehicle like this -- it's an opportunity that comes not so often, I guess, and so it was hard to turn it down."
The actress is especially proud to be a role model for her 3-year-old daughter, Rose. Johansson recently announced her split from Rose's father, Romain Dauriac.
"I am so proud to do a job that I love to do and that I've worked really hard at to get where I am and to be able to show my daughter that and have her come to the workplace and see that her mom is an independent woman making it happen," she said. "It's really important for me."
"It's important to have levity in life in general, and it helps bring people together -- certainly laughing," Johansson said. "'SNL' has been killing it this season. It was really awesome to bring some topical skits to the live audience."