ANATOMY UNIT 4: Skeletal System

Functions of bones

Support, protection, movement, storage, blood formation.

3 types of conn tissue

bone, cartilage, ligaments

long bones

longer than wide, humerus, femur, tibia

short bones

cube like, support and stability, wrist carpals, foot tarsals

flat bones

thin, support and protection, cranium, ribs

irregular bones

complex, flexible movement, vertebrae, coccyx, ear bones

sesamoid bones

small and round, protection of tendons, patella

diaphysis

shaft of a long bone

Epiphysis

End of a long bone

Metaphyses

regions between the diaphysis and the epiphyses

periosteum

Double-layered connective tissue that covers outer surface and provides protection

articular cartilage

thin hyaline, reduce friction and absorb shock

compact bone

found on the outside of the bone, osteons

spongy bone (red marrow)

Located in epiphysis, has rods or plates called trabeculae and cavities filled with red bone marrow

condyle

round end of bone, not sep by neck

facet

flat smooth surface

head

round smooth end of bone, includes a neck

crest

Narrow ridge of bone; usually prominent

Epicondyle

Raised area above a condyle

line

narrow, elongated ridge on a bone, less prominent than a crest

spine

sharp, slender projection

Tubercle

small rounded projection

tuberosity

large, round , and usually rough projection

trochanter

large, blunt, irregular surface

ramus

arm like bar of bone

fissure

slit thru a bone or between 2 bones

formamen

hole in a bone

fossa

shallow depression

meatus

a tube-like passageway through a bone

sinus

air filled space within a bone

sulcus/groove

groove within a bone

3 parts of bone tissue

extracellular matrix(mineral salts), fibers( collagen fibers),cells(living part)

osteoclasts

Bone-destroying cells

osteogenetic cells

stem cells that differentiate into osteoblasts

osteoblasts

Bone building cells

osteocytes

Mature bone cells that maintain bone tissue.

bone extracellular matrix

inorganic(crystels that calcify on fibers) and organic ( ground substance), laid down by osteoblasts

collagen fibers

provide a framework

cartilage tissue

hyaline, consists of specialized cells called chondrocytes

hyaline cartilage

found at joints, support, flexibility, movement

ligaments

Connect bone to bone, support and stability

compact bone structure

forms hard exterior of all bones, rings organized into osteons

central canal

contains blood vessels and nerves

spongy bone structure

forms inner layer of all bones, epiphysis, trabeculae, gives strength

intramembranous ossification

1)dev of oss center ( osteoblasts secret extra cell matrix)

2) hardening of bone by deposition of calcium and salts

3) form trabeculae that fuse to form bone

* NO CARTILAGE IN THIS STAGE

endochondral ossification

most of bones formed by this

1) secretion of cartilage

2) growth of cartilage by cell division

3) dev of primary oss center

4) bone tissue replaces cartilage

5) dev of marrow cavity

6) dev of a second oss center

7) form articular cartilage

factors affecting bone growth

bone remodeling, adequate amounts of calcium, phosphorus, magnesium, hormones like hGH and thyroid, excercise

bone remodeling

replace old bone through bone resporption by osteoclasts followed by deposition of osteoblasts

Bone's Role in Calcium Homeostasis

Bone is the body's major calcium reservoir

Levels of calcium in the blood are maintained by controlling the rates of calcium resorption from bone into blood and of calcium deposition from blood into bone

complete fracture

bone is broken all the way through

incomplete fracture

bone is not broken all the way through

Green stick fracture

incomplete fracture

compound fracture

bone breaks through the skin

simple fracture

bone is broken cleanly; the ends do not penetrate the skin

transverse fracture

fracture at a right angle to bones axis

oblique fracture

a fractured in which the break slopes

spiral fracture

bone has been twisted apart

Communitied fracture

a fracture in which the bone is broken, splintered, or crushed into many pieces

treatments for fractures

reduction, immobilization, restoration of function

scoliosis

lateral curvature of the spine

kyphosis

thoracic curve

lordosis

lumbar curve

spina bifida

failure of neural tube to dev properly, paralysis

osteoporosis

loss of bone density

herniated disc

protrusion of a fragmented intervertebral disc in the intervertebral foramen with potential compression of a nerve

osteogenetic sarcoma

bone cancer most common in children

rickets

childhood disorder softening and weakening the bones

rheumatoid arthritis

a chronic autoimmune disorder in which the joints are attacked

Osteoarthritis

chronic arthritis, aging

transverse

link central canals

lacunae

small areas that contain osteocytes

canaliculi

passageways connect lacunae together, intercellular communication between osteocytes