What are the 6 functions of bone?
1. support structure, framework, provide for muscle attachment
2. Lever System ( function as levers to allow for movement)
3. protection of vital organs
4. storage of minerals (calcium, phosphate)
5. storage of fat (yellow bone marrow)
6. produces blood c
What is the shaft or the long middle portion of a long bone called?
Diaphysis
An end of a long bone is called a
Epiphysis
There are two epiphyses, a __________ and ___________ end.
proximal, distal
What is the flared portion of the shaft that connects to the ends called?
Metaphysis
The boundary of Metaphysis and Epiphysis
epiphyseal line
Where is articular cartilage located?
located on ends of bones, smooth
What is the purpose of articular cartilage?
to reduce friction
What does periosteum surround?
surrounds bone
How many layers of periosteum are there? What are they?
1. Collagen
2. Mesenchyme
Collagen surrounding bone is made of what type of CT?
made of fibrous CT
Which layer of periosteum is the outer layer?
collagen is the outer layer
Which layer of periosteum is the inner layer?
mesenchyme is the inner layer
Collagen surrounding bone allows for what?
Allows for vessels and nerves to pass into bone
The mesenchyme layer of periosteum contains what type of cells?
contains osteoprogenitor cells
osteoprogenitor cells are bone specific _______________ cells.
mesenchymal cells
osteoprogenitor cells support what kind of growth?
support appositional growth
What is the medullary cavity?
inner hollow space in the shaft of the diaphysis filled with yellow marrow
What is endosteum?
the layer of CT that lines medullary cavity
- contain osteoprogenitor cells as well
- "inner" layer
The periosteum surrounds the outside of the bone, whereas the endosteum surrounds the ___________ of the bone.
inside
What type of tissue is bone?
connective tissue
If bone is CT, then what does that mean it is made out of?
made of cells and IC substance
What is the IC substance of bone made of?
made of collagen, elastin & calcium salts
the collagen in the IC substance of bone is strong against...
strong against tension
the calcium salts (tricalcium phosphate & calcium carbonate) in the IC substance of bone are strong against...
strong against compression
What is the exterior bone made of?
Made up on compact, hard bone
Where is the exterior bone thicker at on the bone?
thicker in diaphysis
Why is the exterior bone thicker in the diaphysis?
it is thicker to provide extra support and decrease risk of injury in our long bones
Interior bone looks _________ in appearance
spongey
Spongey bone (interior bone) is usually found in what places?
found in epiphyses and flat bones, such as skull and ilium
spongy bone is also called...
also called cancellous bone
What are the 4 bone cells?
1. Osteoprogenitor
2. Osteoblasts
3. Osteocytes
4. Osteoclasts
Osteoprogenitor cells
bone specific stem cells derived from mesenchyme, can divide to form other bone cells (specifically blasts/clasts)
Osteoblasts
form/build bone, secrete IC substance/matrix (once they become surrounded by matrix, they become an osteocyte)
Osteocyte
maintain structure & function of bone (no IC substance produced)
Osteoclasts
break down/destroy bone (also called resorption
- bone eaters
bones are constantly "remodeling"... what does this mean?
bones are constantly being broken down and new bone being rebuilt as we grow
Osteon/Haverian System
functional unit of compact bone
- work togethers to maintain structure of bone
There are 4 major structures of an Osteon (Haverian System)... what are they?
1. Haverian Canal
2. Lamellae
3. Lacunae
4. Canaliculi
Haverian Canal
extends length wise through the center of the osteon
- contains blood vessels, lymph vessels & nerves
Lamellae
surround canal, several layers of calcified matrix
Lacunae
sack like space filled with fluid (lake like) between Lamellae that house the osteocytes
Canaliculi
crack like, radiate out from Lacunae to connect osteocyte with other Lacunae & the Haverian canal
Look at powerpoint and drawing to understand the structure of the what?
to understand the structure of the osteon
Volkmann's canals penetrate the compact bone in what way?
penetrate the compact bone transversely or perpendicularly
Volkmann's canals provide a route for what?
provide a route for blood vessels
The Volkmann's canals meet up with Haversian canals to make a way for the...
blood vessels
What do the Volkmann's canals also meet up with?
meet up with the medullary cavity
Spongy bone is also called what?
cancellous bone, trabecular bone
spongy bone is _______ to compact bone
deep
T/F Spongy bone contains osteons
False: spongy bone contains no true osteons
What does spongy bone contain instead of osteons?
needle-like bony spikes called trabeculae
red bone marrow fills the "sponge", nourishes the cells and surrounds the bone cells in ___________ bone
spongy
T/F spongy bone contains lucunae & canaliculi
True
Where can you find spongy bone?
- flat, short & irregular bone
- epiphyses of long bones
What are the 6 different types of bones in the human body?
1. Long bones
2. Short bones
3. Flat bones
4. Irregular bones
5. Sesmoid
6. Wormian bones
Long bones
levers (ex: phalanges, femur, tibia, humerus, metacarpals)
Short bones
cube shaped bones (bones in wrist & ankle --> tarsals, carpals)
Flat bones
look like a sandwich, parallel layers of compact bones separated by spongy bone (ex: ilium, scapula, ribs, sternum, clavicle)
Irregular bones
peculiar/irregular shaped (ex: vertebrae, ischium, ethmoid)
Sesmoid bone
floats within a fascia or tendon (ex: patella)
Wormian bones
specific to skull, sutural, little tiny bones formed by extra sutures, not present in everyone, extra, small sutures