What are the 6 primary functions of the skeletal system?
1. Support
2. Storage of minerals and lipids
3. Blood cell production (red bone marrow)
4. Protection
5. Hormone production
6. Leverage (change direction and magnitude of force from muscles)
What type of tissue makes up yellow bone marrow?
adipose
What are the 3 mains types of cartilages?
1. Hyaline
2. Elastic
3. Fibrocartilage
Which type of cartilage:
is most common
has a matrix that appears glassy, blue-white
is stiff but has flexible support?
Hyaline
Which type of cartilage:
is like hyaline but with many more elastic fibers
tolerates distortion without damage?
Elastic
Which type of cartilage:
resists compression
prevents bone to bone contact
limits movement?
Fibrocartilage
Which type of cartilage is in your ear?
Elastic
Which type of cartilage is in your nose?
Hyaline
Which type of cartilage is in your joints?
Hyaline
Which type of cartilage is between your intervertebral discs?
Fibrocartilage
Which type of cartilage makes up your costal cartilage on your ribs?
Hyaline
Which type of cartilage makes up your pubic symphysis?
Fibrocartilage
Which type of cartilage makes up your meniscus?
Fibrocartilage
What are the 2 groups in bone classification?
Axial and Appendicular
To talk about bones we must look at their:
shape
feature surface markings
internal structure
On average, how many bones are in the adult human body?
206
What are the 6 broad categories of bones based on their shape?
1. Sutural
2. Sesamoid
3. Irregular
4. Short
5. Flat
6. Long
Which bone shape is:
also known as wormian bones
small, flat, irregularly shaped
between flat bones of the skull
vary between individuals in number and shape
basically small bone chips
Sutural
Which bone shape is:
small, flat
develop inside of tendons
near joints
vary in number and location with 1 exception
Sesamoid
What is the 1 exception to the sesamoid shaped bones?
patella
Which bone shape is:
complex shapes
short, flat, notched, or ridged
vertebrae, pelvic bones, some skull bones
Irregular
Which type of bone shape is:
small and bony
in carpals and tarsals
Short
Which bone shape is:
thin parallel surfaces
protection for underlying soft tissues
provide surface for muscle attachment
skull, sternum, ribs, scapula
Flat
Which bone shape is:
long and slender
in appendages
includes the larges bone of the body
Long
Where can you find irregular bones?
vertebrae, pelvic bones, some skull bones
Where can you find short bones?
carpals and tarsals
Where can you find flat bones?
skull, sternum, ribs, scapulae
Where can you find long bones?
femur, humerus, metacarpals/tarsals, radium, etc.
What are some characteristics of internal and external bone marking features?
elevation
projection
depressions
grooves
tunnels
etc.
What type of cartilage surrounds the compact bone?
articular
What are the parts of the typical long bone?
Diaphysis
Epiphyses
Metaphyses
Medullary cavity
Periosteum
Diaphyses
the shaft of the long bone
Epiphyses
the heads or ends of a long bone
Metaphyses
the neck of a long bone; where the diaphysis and epiphyses attach
medullary cavity
central cavity of a long bone; contains yellow or red bone marrow
endosteum
connective tissue membrane covering internal bone surfaces
inside the medullary cavity
periosteum
double-layered connective tissue that covers and nourishes the bone
Where is the periosteum NOT located in the bone?
joints
Supporting connective tissue contains:
specialized cells
extracellular protein fibers
ground substance
Bone matrix contains __________ salts.
calcium
Osteoid before __________
calcification
osteoid
uncalcified bone matrix
osteocytes
bone cells
lacunae
small open space in the matrix
canaliculi
small holes that allow for the exchange of materials
Osteocytes are within the lacunae except for...
canaliculi
True or false.
Bone matrix in compact bone is the same as in spongy bone.
True
In the bone matrix, cells account for about __% of mass.
2
___________ fibers provide framework in the bone matrix.
collagen
What are the 4 types of bone cells?
1. osteocytes
2. osteoblasts
3. osteoprogenitor cells
4. osteoclasts
Which type of bone cell is:
mature bone cells (majority of cells)
occupy lacuna surrounded by lamellae
cannot divide
osteocytes
Where can you find osteocytes?
canaliculi
What are the 2 major functions of osteocytes?
1. maintain protein and mineral content of matrix
2. participate in repair of damaged bone
Which type of bone cell:
produces osteoid
elevates Ca phosphate levels above solubility limit
osteoblasts
lamella
layers of calcified matrix
osteoblasts calcify themselves into __________.
osteocytes
Osteocytes are ___________ surrounded by bone.
osteoblasts
Which type of bone cell:
is squamous stem cells
daughter cells differentiate into osteoblasts
important in fracture repair
osteoprogenitor cells
Where can you find osteoprognitor cells?
inner layer of periosteum and endosteum
Which type of bone cell:
remove and recycle bone matrix
giant cells with 50+ nuclei
derived from stem cells that produce monocytes
bone breaking cells
osteoclasts
_______________ are building up bone mass while ________________ are breaking bone mass.
Osteoblasts, osteoclasts
Which cell type is a stem cell?
osteogenic cell
matrix- synthesizing cell responsible for bone growth
osteoblast
mature bone cell that monitors and maintains the mineralized bone matrix
osteocyte
bone-resorbing cell
osteoclast
How are osteocytes arranged in compact bone?
concentric layers
osteon or Haversian system
the structural unit of compact bone
central or Haversian canal
runs through the core of each osteon; contains small blood vessels and nerve fibers that serve the osteon's cells
perforating or Volkmann's canals
lie at right angles to the long axis of the bone and connect the blood and nerve supply of the medullary cavity to the central canals
What are the 2 types of canals in compact bone?
1. Central canal or Haversian canal
2. Perforating canal or Volkmann's canal
What are the 3 types of lamellae?
1. Concentric
2. Interstitial
3. Circumferential
Concentric lamellae
around central canal
Interstitial lamellae
fill in the gaps of between forming osteons
Circumferential lamellae
outside surface of the bone
trabeculae
forms meshwork of bundle fibers in spongy bone
True or false.
Spongy bone contains no capillaries or venules in its matrix.
True
Where does diffusion occur in spongy bone?
along canaliculi
What are the 2 types of bone marrow?
1. Red
2. Yellow
Which type of bone marrow is between trabeculae?
red
hematopoeisis
the formation of blood cells
Where does hematopoeisis occur?
red bone marrow
True or false.
Red bone marrow can transition into yellow bone marrow as you get older but can transition back if needed.
True
What is the time period for bone growth and development?
6 weeks after fertilization until around 25 years old
ossification or osteogenesis
deposition of calcium salts into hyaline cartilage
Development and growth of bone depend on the balance between:
bone formation and bone resorption
osteoblast and osteoclast function
What are the 2 types of ossification?
1. Membranous/ Intramembranous
2. Endochondral
membranous ossification
mostly flat bones
skull bones and scapula
ednochondral ossification
replacing of hyaline cartilage with ossified bone matrix
exercise stimulates the ___________, making them stronger
osteoblasts
What are the 5 stages of endochondral ossification?
1. Bone collar around diaphysis
2. Primary ossification center in center of diaphysis
3. Periosteal bud invades cavity
4. Diaphysis elongates and marrow cavity forms
5. Epiphyses ossify
At which stage in endochondral ossification does spongy bone form?
3. Periosteal but invades cavity
When children are born, their epiphyses are completely ____________ cartilage.
hyaline
What happens during appositional growth?
there is an increase in bone diameter
What causes the increase in bone diameter during appositional growth?
inner layer of periosteum differentiates into osteoblasts
At epiphyseal plate, chondrocytes produce __________.
cartilage
chondrocyte
mature cell of cartilage
During ____________ growth, osteoblasts turn cartilage into bone.
longitudinal
True or false.
So long as chondrocytes stay ahead of osteoblasts, bone elongates.
True
At puberty, hormones speed up ___________.
osteoblasts
Fractures may be classified by:
Position of bone ends after fracture
Completeness of fracture
Whether bone ends penetrate skin
Type of fracture
comminuted fracture
bone fragments into 3 or more pieces
When are you most likely to see a comminuated fracture?
in the elderly
compression fracture
bone is crushed
Where are you most likely to find a compression fracture?
common in porous bones; bones subject to extreme trauma, as in a fall
spiral fracture
ragged break occurs when excessive twisting forces are applied to a bone
What is the most common way to get a spiral fracture?
sports
epiphyseal fracture
epiphysis separates from the diaphysis along the epiphyseal plate
Where do epiphyseal fractures tend to occur?
where cartilage cells are dying and calcification of the matrix is occurring
depressed fracture
broken bone portion is pressed inward
Where are depressed fractures most typical?
skull
greenstick fracture
bone breaks incompletely; only one side of the shaft breaks, the other side bends
Greenstick fractures are most common in what age of people?
children and athletes of upper teens and early 20s
4 major stages of simple fracture repair:
1. Hematoma forms
2. Fibrocartilaginous callus forms
3. Bony callous forms
4. Bone remodeling occurs
When talking about fracture repair, what does reduction mean?
the lining up of the broken ends of the bone
complex fracture
you have to line the bones up so they can grow back together
simple fracture
bones are close enough together to grow back on their own
At what stage during simple fracture repair may you be able to remove a cast?