What are the functions of the skeletal system?
-Support and protection -Body movement -Blood cell formation (hematopoiesis) occurs in bone marrow -Storage of inorganic materials (salt, calcium, potassium)
How many ones are you born with and how many do you have now?
You are born with about 270 but they fuse together to make 206
What does the axial skeleton consist of?
-Head, neck, trunk -Skull -Hyoid bone -Vertebral column -Thoracic cage (ribs, 12 pairs) -Sternum
What does the appendicular skeleton consist of?
-Pectoral Gridle (scapula, clavicle, arms) -Pelvic Gridle (coxal bones, legs)
What does fibrodysplasia ossificans progressiva (FOP) cause?
Causes soft tissue (muscles, tendons, ligaments) to turn to bone
What does the long bone consist of?
-Epiphysis (end) -Diaphysis (shaft) -Articular Cartilage (hylaine cartilage, padding) -Periosteum (membrane that covers entire bone) -Medulla (contains marrow)
How are the epiphyses named?
By location
Closest epiphyses to the body's central ->
Proximal
Furthest epiphyses from the body's central ->
Distal
What is the function of flat bones? Give example
Protection -- sternum, ribs, skull, bones
What is the function of long bones? Give example
Support weight, movement -- femur, tibia, fibula, humerus, radius, ulna
What is the function of short bones? Give example
Stability, movement -- carpals, tarsals
What is the function of irregular bones? Give example
Protects organs -- vertebrae, pelvis
What is the function of sesamoid bones? Give example
Reinforce tendons -- patella (knee cap)
What is inside the long bone?
-Medullary Cavity: hollow, filled with yellow bone marrow -Endosteum: lines of the medullary cavity -Red Marrow: produces blood -Yellow Marrow: fat storage
What are the types of bone tissue?
-Compact (wall of the diaphysis) -Spongy/Cancellous (epiphysis) -> red marrow
What is the epiphyseal line?
The growth plate
What is bone tissue called?
Osseous tissue
What is the matrix composed of?
Collagen and inorganic salts
What is osteocytes?
Mature bone cells, enclosed in tiny chambers called lacunae
The rings that form around the osteocytes are called?
Lamellae
What does the haversian canal house?
Blood vessels
What is a canaliculi?
Tiny canals that link osteocytes
What provides passageways for blood vessels?
Haversian and Volkmann canals
What is the process ossification?
Bone first forms as hyaline cartilage, then gradually changes into bone tissue
Primary ossification center increases...
Diameter
Secondary ossification center increases...
Length
Osteoblasts:
Creates osteocytes (blasts = produce)
Osteoclasts:
Bone resorption (clasts = destroy)
Define epiphyseal disk (growth plate)
A bond of cartilage between the epiphysis and diaphysis
Name the types of joints
-Synarthrotic: immovable joint, called sutures -> skull -Amphiarthrotic: slightly movable -> vertebrae -Diarthrotic (synovial joint): movable joint -> knees, elbows, wrist, shoulder
Name the types of diarthrotic joints
-Ball & Socket joint (shoulder, hip) -Hinge (elbow, knee) -Pivot (lower arm) -Saddle (thumb)
Frontal bone
Anterior portion (forehead)
Parietal bone
On each side of the top of skull
Temporal bone
Side, above ear
Occipital bone
Forms the back of the skull
Sphenoid bone
Within the cranium, party visible in
Ethmoid bone
Nasal cavity, visible in eye socket
Maxilla bone
Forms upper jaws
Mandible bone
Lower jaws, only movable bone of the skull
Zygomatic bone
Cheek bone
Vomer bone
Small, thin, plow-shaped, midline bone that occupies and divides the nasal cavity
Define sutures
Connection points between skull bones
Coronal suture
Between frontal and parietal bones
Lambdoidal suture
Between occipital and parietal bones
Squamosal (squamous) suture
Between temporal and parietal
Sagittal suture
Between parietal bones
What are fontanels?
"Soft spots" of an infants skull, these form sutures as you age, top spot is the anterior fontanel
What is the mental foramen?
An opening on the chin that allows nerves and blood vessels to come through to supply face