Structure of Long Bones Flashcards
What are the layers within diaphysis (shaft)?
- Periosteum
- Compact bone
- Endosteum
- Medullary (marrow) cavity
Periosteum
Most superficial layer
Acts as an anchor for tendons and ligaments
Contains blood vessels and nerves
Compact Bone
2nd and thickest layer of the diaphysis
Full of osteocytes
appears very dense but the microscopic view displays a complex arrangement of canals known as the Haversian System
Endosteum
3rd layer of the diaphysis
Covers the inner layer of compact bone
Contains both osteoblasts and osteoclasts
Medullary (marrow) Cavity
The deepest layer of the diaphysis
Contains bone marrow
Infant medullary cavities contain red bone marrow for blood product
Adult medullary cavities contain yellow bone marrow for fat storage
What is the Haversian System?
Passageways for nerves and blood vessels. The passageways are known as osteon
Where is red bone marrow found?
In the spongy bone of flat and/or irregular bones
What happens when an individual is anaemic?
The body converts yellow bone marrow back to red bone marrow dor increased blood production
What are the layers within epiphysis (bone end)?
- Articular Cartilage
- Spongy Bone
- Epipyseal Line
Articular Cartilage
The most superficial layer of the epiphysis and is covered by the hyaline cartilage
Spongy Bone
2nd and thickest layer of epiphysis
Lies under a thin layer of compact bone
Spaces contain red bone marrow to produce blood
Epiphyseal Line
Located between the diaphysis and each epiphysis of adult long bones
Remanent of the epiphyseal (growth) plate
What is the role of hyaline cartilage?
To absorb stress and decrease friction between bones during movement
What is the role of trabeculae?
To withstand stress and support the compact bone
When does hyaline cartilage begin to grow?
Hyaline cartilage grows during childhood to length bone
