Bernadette suggests that Howard go on a fishing trip with her father, as an opportunity to bond with him. However, since Howard doesn't know anything at all about fishing or cleaning fish, the guys seek advice on the manly art of fishing from the only source they can think of: Penny.
Meanwhile, when Amy is sick, Sheldon is convinced it's his responsibility to take care of her. However, when Amy realizes that this is a way of getting physical interaction from Sheldon on a level heretofore prohibited to her, she begins faking the illness to extend the positive side effects of the experience. When Sheldon finds out about her act of subterfuge, he decides that discipline must be maintained with corporal punishment and Amy relents because, after all, she has been a bad girl ... a very bad girl.
This Episode's Science
Doctorate - When Amy asks Sheldon to take care of her when she's sick, he replies that he's "not that kind of doctor." This is a joke about the fact that Sheldon has a Ph.D. in theoretical physics, thus earning him the title Dr. Sheldon Cooper, though he does not have an M.D. that allows him to practice medicine. Despite this (and his poor bedside manner), Sheldon finally consents to take care of Amy in her time of need.
Placebo Effect - At one point, Sheldon attempts to cure Amy through use of the Placebo Effect, though he makes the mistake of being too apparent in the attempt. The Placebo Effect is the effect in medicine where a treatment that has no medical curative power, but which still results in a physical recovery from the patient as if it had been an actual treatment that was effective in its own right. When conducting medical research, medicines are compared against a control group (who often receive sugar pills or other non-reactive "treatments"). The ideal evaluation of the results involves not just seeing the recovery from the "real" therapy, but also comparing that recovery rate to the recovery rate among the placebo group.
Etruscans - When Leonard is complaining about his father's inattentiveness, he points out that as an anthropologist, his father spent more time with an Etruscan boy than with him. The Etruscans were an ancient people.
Amy: Sheldon, aren't you going to take care of me?
Sheldon: Me? No. I'm not that kind of doctor.
Amy: But our relationship agreement clearly states that when one of us is sick the other must take care of them.
Sheldon: Oh, I see the confusion. The intent behind that clause was to force you to take care of me when I'm ill. When you're feeling better, you'll think that's funny.