I was teaching a class of fifth grade students last week and we were discussing the characteristics of DNA and cells. As a group, we described how the human body is made up of a variety of cell types, including muscle cells, nerve cells, and more. I explained that although cells can be diverse in their appearance and functions, within one organism they all have the same DNA (except for mature red blood cells and gametes). The reason that a nerve cell is different from a bone cell is simply that they use different recipes in different ways.

A student then More >