Penny: Sweetie, let me put this in a way you'll understand. From the waist down, my shields are up.

Leonard: What am I supposed to do?
Penny: Err, keep your mouth off other women.

Penny: At one point, they had me figure out how to get a banana out of a puzzle box.
Leonard: Wait, Sheldon gave me a banana in a box. He was testing me, too.
Penny: Unbelievable.
Leonard: And how could a chimp even solve that? That was impossible.
Penny: Really? You couldn't get it out?

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Howard: What, I'm not hot enough for Angelina Jolie?
Raj: Id like to weigh in here: No.

Sheldon: Good morning everyone and welcome to "Science and Society". I'm Dr. Sheldon Cooper, BS, MS, MA, PhD and ScD. OMG, right?

Amy: Are you in the lanthanide series?
Sheldon: Amy, it's Penny's turn. Penny.
Penny: Uh, I dunno. Are you food?
Sheldon: That's not a apropos! We've already established I'm found on the Periodic Table.
Penny: Well, it's a table, right? I mean, why can't there be food on it?
Sheldon: I knew she wasn't lead car material.