Sheldon: The thing about tomatoes, I think you will really enjoy this, is that they are shelved with the vegetables but they are technically a fruit.
Penny: Interesting.
Sheldon: Isn't it!
Penny: No, I mean what you find enjoyable.

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?

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

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

Mary: He gets his temper from his daddy.
Leonard: Ah.
Mary: He's got my eyes.
Leonard: I see.
Mary: All that science stuff, that comes from Jesus.

Mary Cooper: I'm sorry, did I start that sentence with the words, "If it pleases your highness?"

Sheldon: I read an article about Japanese scientists who inserted DNA from luminous jelly fish into other animals; and I thought "Hey! Fish night-lights".
Leonard: Fish night-lights.
Sheldon: It's a billion dollar idea, ssh!