Follow This is a tale that revolves around you. A narrative that takes place on the interior of your body... A recent study estimates that the human body is comprised of roughly 37 trillion different cell types. Within the world that is your body, these cells toil away at their jobs day in and day out. Learn about the unsung heroes and the drama that plays out inside of you, starting with the Red Blood Cells that deliver oxygen and moving on to the White Blood Cells that battle bacteria.