Hank explains the function of mitochondria and what makes it so cool. He also explains how scientists can find out our ancestors using mitochondrial DNA.

Brian Cox explains the origin of the mitochondrial symbiotic relationship with the cell. He starts with introducing the nucleus and gives context to the early cell types - prokaryotes and eukaryotes. Brian then explains what scientists believe was the beginning of a symbiotic relationship where a bacteria enters an archaea. 

Hank explains the inner workings of a eukaryotic cell and the role of several organelles. He compares the way a cell functions to a city with a fascist government, which he calls "Eukaryopolis." Key Words: Eukaryote, Prozac, Flagellum, Cilia, Microtubules, Cell Membrane, Cytoplasm, Centrosome, Nucleoplasm, Vesicles

The virus inside Cyborg tried to attack a cell that multiplied to fight the virus. The cell that multiplied went throughout his body to his nose and Cyborg sneezed out the virus. He was no longer controlled by the virus and he felt better.

Hank explains active and vesicular transport then covers how cells regulate their contents and provide means to transport mechanisms.