The fibrous connective tissue that makes up the outside covering of the diaphysis is the

fibrous periosteum

The diaphysis is the main shaft of a long bone which is made up of cortical bone which contains bone marrow and fats. It is covered by a fibrous connective tissue called the fibrous periosteum. The cells in this layer are densely packed and contain blood vessels, nerve endings and lymphatic.  

d. organisms have cells with different shapes and functions.