Explain how human embryonic stem cells, adult stem cells, and skin cells taken from the same person would be the same and how they would be different. explain what causes the differences you describe.

All three cells would be similar since they all share the same hysteroscopic pathology being that they are all from the same individual. However, the ways in which they are different are vast and can be described ad nauseam. Suffice it to say that an embryonic stem cell is the most pure form of a cell, and can be used in a variety of different stem cell therapies for that reason. The skin cells would be most useful in terms of skin grafts, while adult stem cells are found only in mature individuals (ie: adults) and have little purpose other than supplying the organism with energy storage capacities.The differences briefly described here are due, in large part, to the tenets of the cell theory which states that all organisms, whether single celled or otherwise, are comprised of one or more cells containing DNA. 

Covalent bond is the correct answer