Week 5 Flashcards
(39 cards)
What are the 5 functions of bone?
Structural foundation
Mobility
Support
Protection
Storehouse for essential minerals
What is the end of a long bone called?
Epiphysis
What does diaphysis mean?
The shaft of the bone
What is a medullary
The hole in the bone
What is a endosteum
A sheeth
What is the matrix of bone?
25% water, 25% collagen and 50% crystallised mineral salts, calcium hydroxyapatite
Another word used for compact bone?
Cortical
Another word for spongy bone
Trabecular or cancellous
What percentage does compact (cortical) make up of the bone mass?
80%
Trabecular bone makes up what percentage of bone mass
20%
What is the periosteum
Vascular membrane, inner layers contain osteoblasts and osteoclasts and the outer layer is tough and fibrous.
What does the Haversian canal contain?
Blood vessels and nerves
What is the lunellae
Series of cylindrical plates arranged around a central canal
Lacunae
Strings of little cavities in which osteocytes sit
Canaliculi
Tiny network of channels which allows the lacunae to communicate. Allows for interstitial fluid to circulate through the bone and direct contact between osteocytes
Which type of bone withstands stress better
Spongy bone
What are the four types of bone cells
Osteogenic/osteopogenitor cells
Osteoblasts
Osteocytes
Osteoclasts
Where are osteogenic cells found
Endosteum, inner layer of periosteum
Undifferentiated cells
Where are osteoblasts found in
Surface of bone than in lacunae
They build the matrix and collagen fibres
Osteoclasts
Clear bone cells. Biggest of the bone cells. Reabsorb dead bone cells to clear deadbry
What are the four types of blood supply to bones
Periosteal arteries
Nutrient arteries
Metaphyseal arteries
Epihyseal arteries
Where are periosteal arteries found
Periosteum and outer osteons of compact bone
Where are nutrient arteries found
Medullary cavity and osteons of inner compact bones
Where are metaphseal arteries found
Spongy bone and marrow
