My first encounter with a gender bias issue at work was 14 years ago at a previous firm when I was hiring for a job and using a recruiter. After a couple of interviews with folks that weren't for what I was looking, the recruiter, a woman, emails me and says, "I found the perfect person for you, and the best part is... she is gorgeous!".
I called her up and said, now you have made hiring this person much more difficult, you realize you cannot say things like that, right? So, I hung up and arranged interviews with this person and three of my female staff members who indicated they thought her job knowledge skills were strong before I interviewed her.
Second encounter with a gender bias issue was when one of the other temps started sexually harrassing this woman a few weeks after I brought her on. I let him go that day.
I have regularly seen in my career and in non work situations where if you have a meeting, men feel like they can cut women off or talk over them. I usually wait until I get a chance to speak and say "I have a number of things I would like to add, but I would really like to hear what she (the woman who was cut off) had to say."