Sheldon tries to help Penny understand Leonard's work at the University. Howard becomes jealous when Leonard becomes close with his new girlfriend.
- The Art of Bra Removal: Howard tries taking out Bernadette's bra while they're kissing in his bed. Bern tells him that it actually unhooks in her front.
- Big "NO!": When Bernadette (who is new to the main cast here) goes to sit in Sheldon's spot, everyone objects.
- Blatant Lies: Sheldon complains he has no time to teach Penny any physics. But then Penny retorts he spends all day playing video games when he's home and never does research outside work.
- Commonality Connection: Leonard and Bernadette immediately become friends as they quickly bond over Leonard's work. Bernadette recommends the solution of applying tunnel junctions for his work on the Aharonov-Bohm quantum interference effect, and Penny is befuddled by what they're talking about and she gets inspired to learn physics herself so that Leonard won't fall for Bernadette.
- Green-Eyed Monster:
- Howard when Leonard is able to entertain and impress Bernadette better than he can.
- Penny as well towards Bernadette for gaining Leonard's respect knowing far more about his work on quantum interference.
- Grotesque Cute: Sheldon is disgusted when he observes Bernadette and Penny flirting with each other's fashion and shoes.
- Interrupted Intimacy: Bernadette and Howard get interrupted in bed by both Mrs. Wolowitz's screaming and then Leonard texting Bernadette that the demonstration is off after Howard attacked him for attracting her attention. Bernadette storms out in retaliation and has him just eat lamb stew with his mom alone.
- Jerkass Ball: Howard for bullying Leonard telling him to stay away from Bernadette.
- Namesake Gag: Penny thinks Fig Newtons are named after Isaac Newton. Sheldon corrects her, saying they were actually named after the town where they were invented.
- Never My Fault: Howard scares Leonard into calling off showing Bernadette his work on experimental physics out of jealousy that Bernadette has taken an interest into Leonard's work. Leonard texts Bernadette that Howard is jealous of him, thus ending sex between her and Howard, and she storms out of Howard's house because she's concerned Leonard is being bullied by Howard. Then Howard goes to blame Leonard for everything. Bernadette arrives and claims that Howard called Leonard's experiment stupid. Howard responds to that as he didn't say that, Sheldon said it.
- Shout-Out: Sheldon mentions Koko the gorilla, who was famous for her advanced knowledge of the English language and sign language. The reason why is he's comparing Penny to a great ape for her vacuity in physics.