Seimei no Kagaku: Micro Patrol
English title: Once Upon a Time... Life
Japanese title: 生命の科学ミクロパトロール
Type: OVA
Episodes: 26
Source: Unknown
Genres: Adventure
Studios: Eiken
Producers: Procidis
Duration: 25 min per ep
Rating: G - All Ages

The series "Once Upon a Time... Life" teaches about the human body and about the different systems in it with the same characters from the other "Once Upon a Time" seasons. "The good Characters" represent the body's defense mechanisms, whereas "the bad Characters" represent the viruses and bacteria that threaten to attack the human body.

(Source: Wikipedia)