chapter 5 quiz

closed facture

broken bone that doesn’t penetrate the skin

compound (open) fracture

broken bone ends penetrate the skin

• affects skin, muscles, & tissues

• high risk for infection

comminuted

bone breaks into many fragments/shatters

• common in elderly and brittle bones

compression

bone is weakened and crushed by another bone

depressed

broken bone fragment pushed inward

• ex. skull fracture

impacted

broken bone forced into each other

• common in falls

spiral

ragged break occurs from excessive twisting

greenstick

bone breaks incompletely

• common in children

• flexible bones

• bone splinters, bends, or buckles 

transverse

bone breaks in straight like across bone

reduction

treatment for a fracture, realignment of bones

• closed or open

• healing time 6-8 weeks

closed reduction

bone ends are put back together in normal position outside of the body

open reduction

bone ends are put back in normal position via surgery

repair process steps

1. formation of hematoma

2. fibrocartilage callus

3. bony callus forms

4. bone remodeling occurs

formation of hematoma

• blood vessels rupture

• blood filled swelling

• bone cells deprived of nutrition die

fibrocartilage callous

• new blood vessels grow

• disposal of dead tissue

• fibrocartilage callous formed to splint broken bone

bony callous forms

• osteoblasts & osteoclasts migrate to injury 

• bony callous formed

bone remodeling occurs

• bony callous removed

• strong permanent patch formed at injury site 

what is skeleton made of

bone & cartilage

ossification

process of bone formation

• involves two types of cells

osteoblasts

bone forming cells

osteoclasts

bone destroying cells

4 steps of bone formation

1. formation of bone collar and internal bone cavity

2. blood vessels form

3. medullary cavity

4. ossification of epiphysis

1. formation of bone collar & internal bone cavity

• bone forms around hyaline cartilage model

• cartilage replaced by bone to make internal cavity

• carried out by osteoblasts & osteoclasts

3. medullary cavity

• carried out by osteoclasts

• carve out the cavity 

4. ossification of epiphysis

• growth occurs in length and width

  • controlled by hormones 

  • bone tissue added to external

  • bone tissue removed from external 

bone remodeling

• lifelong process

• mature bone tissue removed and new bone tissue added 

  • controlled by 2 mechanisms

1. calcium levels

• blood calcium drops —> osteoblasts break down bone —> releases calcium into blood 

• blood calcium too high —> deposited into bone

2. pull of gravity 

• bones become thicker in bulky muscle areas

• muscles work harder to pull on bones

• bones become stronger

• physically inactive bones loose mass

osteocytes

mature bone cells

lacunae

tiny cavities that house osteocytes

lamella

arrangement of lacunae concentric cells

haversian (central) canal

carries blood vessels and nerves to all areas of bone

osteon or haversian system

each complex consisting of central canal & matrix of rings

canaliculi

tiny canals that radiate outward from the central canal to all lacunae

• connects all bone cells to nutrient supply

perforation (volkmanns) canals

• small channels that transmit blood vessels from periosteum into the bone

• connect central canals

long bones have…

• diaphysis

• epiphyses

• epiphysial plate

diaphysis

makes up long part of long bones

epiphyses

ends of the long bones

• compact bone enclosing spongy bone

epiphysial plate

• flat plate of cartilage

• cause the lengthwise growth of long bones

• seen in young, growing bones

perisotem

dense layer of connective tissue covering bones

• anchors blood vessels

• everywhere except ends of bones

articular cartilage

• type of hyaline cartilage

• covers ends of long bones & where two bones meet

• decreases friction at joints

medullary cavities

• cavity inside bone

• houses bone marrow

  • red & yellow

yellow bone marrow

storage area for fat in cavity of the long bones of adults 

red bone marrow

site of blood cell formation (red & white)

• red marrow turns yellow

• ex. vertebrae, hips, skull, etc…

bone markings

• marks, bumps, holes, & ridges on the surface of bones

• indicates where muscles, tendons, & ligaments are attached

• where blood vessels and nerves pass

  • 2 kinds = projections and depressions/cavities

bone projections

• grow out from bone

• site of muscle and ligament attachments

• help form joints

depressions & cavities

• indentations in bone

• allow passage of blood vessels & nerves

2 types of bones

• compact

• spongy

compact bones

• dense & rigid

• looks smooth

• forms outer shell of most bones

spongy bones

• small needle-like pieces

• open spaces

long bones

• longer than they are wide

• mostly compact bone

  • all limb bones

  • except patella, wrist, & ankle

short bones

• generally cube-shaped

• mostly spongy bones

• bones of the ankle & wrist 

sesamoids

small short bone embedded with tendon

• ex patella

flat bones

• thin, flattened, curved 

• two thin layers of compact bone around spongy bone

  • ex. skull, rib, sternum 

irregular bones

bones that don’t fit into any other categories

• ex. vertebrae, hip bones, most facial bones

skeletal system

includes bones, joints, cartilage & ligaments

• adapted for movement & position

• 2 divisions

  • axial skeleton

  • appendicular skeleton

axial skeleton

bones that form longitudinal axis of body

• skull, spine, ribcage, etc

appendicular skeleton

bones of limbs & attachment points

5 functions of bones

• support

• protection

• movement

• storage

• blood cell formation 

support of bones

form internal framework & cradle organs

protection of bones

protection of soft body organs

• brain, spinal cord, etc

movement of bones

bones act as levers to move body

storage of bones

fat & minerals

• calcium & phosphorous 

blood cell formation

hematopoiesis, occurs in certain bones