This anime shows us how the cells function in our bodies. I was really glad to find out that an anime like this actually exists. The cells have been designed as humans and are shown doing their 'duties' like carrying oxygen, fighting (yes, literally fighting, drawing out bloods) germs etc. This is an epic way to learn bit about biology. While watching this anime, I keep forgetting that the characters are actually cells living in our bodies and not humans. The setting of the inside of the human body is also beautifully done. Many a times, it looks like a factory or the construction site. The way cells are shown getting trained or carrying out their tasks sincerely actually made it look like a job or a task in the 'real world'. Its almost like 'Yes, we too work like this in the human world'. Except, we have at least some time to chill. The trillions of cell work hard in our body all day, every day. Some of the scenes would even remind you of some mainstream Shounens.
This anime is a must watch. Not only it is knowledgeable and educational but it also talks about some work ethics as well.