When Sheldon is sick he tells Penny that his mom couldn't come to Germany when he was sick as a teenager because the cinder blocks shifted the house. According to Young Sheldon however they lived in a nice neighborhood and lived in a normal house that would not have shifted. Furthermore, at the age he said this happened (15), his father had already passed away, so his mother couldn't have helped his father with anything.
When Leonard is placing the sensor next to Sheldon's room, the position of the bag he pulled it out of changes repeatedly. Also, the light on the sensor changes from blue to red between shots.
When sick Sheldon exits his bedroom in the morning, he drops his comforter so it is fully on the raised step. He then goes to the refrigerator and when he exits the kitchen, the comforter is half on the raised step and half off of it.
When Howard first gets out of bed, his comforter and coverlet are neatly folded. The comforter changes to being lifted up and covering half the coverlet without him touching it.
When Sheldon explains that Penny needs to get more data for her joke, she holds a catalog with the spine facing forward. It faces down at an angle in one shot, then is back in its original position in the next.
Sheldon asks Leonard to swab his throat so he can grow a culture, but he believes he has been exposed to influenza, which is a virus. Viruses cannot be cultured.
When Leonard reminds Sheldon to drink plenty of fluids Sheldon attempts to deride Leonard by asking "What else would I drink, gasses...?" Gasses ARE fluids. Liquids and gasses are both fluids. If fact, generally, gasses are more fluid than liquids.
During the cold open 3d chess game, Leonard picks up his knight, replaces it on the board and moves his bishop instead. Under the rules of chess, if you touch a piece deliberately you must move it if it has a legal move.
When Leonard and Sheldon are playing tri-dimensional chess in the cold open, Sheldon is playing black, but there is no black king on the board. The piece he moves to "checkmate" Leonard is his queen, since it moves more than one space.
When Sheldon is making the petri dishes, he says that "someone" ate all the apricot yogurt. He was presumably implying that it was Leonard. However, Leonard is lactose-intolerant.
A life-long mysophobe like Sheldon would not fail to cover his mouth when coughing, yet he fails to do so repeatedly throughout this show.
None of the five Planet of the Apes films reach a runtime of two hours.
When Sheldon talks to Penny about being sick in Germany he says : "The local cuisine was a little more sausage-based than I'm used to, and the result was an internal blitzkrieg, with my lower intestine playing the part of Czechoslovakia." The actual Blitzkrieg was conducted against Poland.
When they enter the theater, Howard complains, "Everyone went chimp." However, a gorilla and an orangutan can be clearly seen in the front row, and another orangutan is visible in the back.