Osteology Flashcards
How are bones classified?
According to shape
According to development
According to Region
What are the regional classifications of bone?
Axial and Appendicular
What are the classifications of bone according to shape?
Long Short Flat Irregular Pneumatic Sesamoid
What are the development classifications of bone?
Endochondral
Intramembranous
What is characteristic of the endochondral classification of bone?
This is the type of bone that replaces a cartilaginous precursor. Mesenchyme would develop into cartilage and then would later ossify into bone.
What is characteristic of the inter membranous classification of bone?
This type of bone grows directly from the mesenchyme tissues, for example, the bone of the skull.
What is characteristic of long bone?
Tubular with a medullary cavity Found in the limbs -Epiphysis -Epiphyseal plate -Diaphysis -Epiphysis ****metaphysis - growth zone cartilage replaced by bone
What is characteristic of short bone?
Cuboidal
Sliding across each other
ex carpals and tarsals
What is characteristic of flat bone?
Protective
ex ribs, sternum, skull
What is characteristic of irregular bone?
irregular in shape - provide many functions - ex zygomatic, sphenoid, mandible, and vertebrae
What is characteristic of pneumatic bone?
Spongy part of bone has been replaced by a cavity (sinus)
ex maxilla
What is characteristic of sesamoid bone?
Bone grown within connective tissue
ex patella
Improves movement
What defines the skeletal system?
The bones and the joints of the body
Adult - number of bones
206
What types of bones cause variation over or under 206 in an adult?
Sesamoid bones
Wormian bones
Accessory bones
What is characteristic of wormian bones?
Bony islands within the suture lines of the skull
What is characteristic of accessory bones?
Cause by ossification centers failure to fuse
How many bones of the axial skeleton?
80 bones
How many bones of the skull?
28 bones
How many ribs?
24 bones
How many bones of the appendicular skeleton?
126 bones
How many bones of the upper extremities?
64 bones
How many bones of the lower extremities?
62 bones
What are the structural types of bone?
Compact
Spongy
