Fill in the Blanks Activity 3Online version Identify the characteristics of the five shapes used in the classification of bones. by Kristani Cochran 1 longbones spongy compact Short patella medullary long red sesamoid perosteum yellow flat cavity marrow diaphysis endosteum irreuglar Bones that are generally greater in length than in width are considered . The is a long cylindrical structure which forms the main shaft of the bone . The central part of this is hollowed to form the or . There are two types of bone marrow : and . Furthermore , bones are formed of two thin plates of covered compact bone , separated by a thin layer of covered spongy bone . bones are generally equal in width and length and mainly composed of bone covered by a thin layer of bone . The bones that are elaborate in shape and can't be classified into any other category are considered bones . Lastly , bones formed within tendons of some muscles as these tendons pass over joints are called bones , for example , the .