Beakmans explains that onions make you cry because of the chemical that gets into your nose. He then uses a schematic of a bathroom drainage system as a metaphor for how your nose, mouth and eyes are all connected. Lester sneezes when his nose was tickled and this causes his eyes to shut because the muscles are connected.

Beakman explains flatulence and why our bodies build up gas that needs to be expelled. He explains how various foods affect the bacteria in the colon and that they release gas and cause it to accumulate. They also mention that the sound of flatulence comes from the anal sphincter.

Beakman explains earwax and its purpose using a giant ear with wax in it and an animated clip. He also explains why your ears pop due to the change in pressure.

Sophie conducts an experiment in which she creates a snot-like substance. She then explains the purpose of snot and provides a fun fact: we have mucus in our eyes.

George pretends to be handicapped, and while riding his bike, he hits a senior man's bike. When confronted by the geriatric biker, he is faced with a choice: fight or flight. He chooses flight.