Bones

206

how many named bones are there

axial 80, appendicular 120

what are the two main divisions of the skeleton

bones along axis

axial skeleton

skull, auditory ossicles, hyoid bone, ribs, breastbone, backbone

what are the bones of the axial skeleton

bones of extremities

appendicular skeleton

upper/lower limbs

what are the bones of the appendicular skeleton

protect internal organs, frames, supports, movement, sound transduction

mechanical function of skeletal system

interaction between bone and muscle

biomechanics

calcium and phosphorus storage, fatty acid storage in yellow marrow, acid base balance, detoxification

metabolic functions of skeletal system

absorb/release alkaline salts

how skeletal system acid base balance

store heavy metals

how skeletal system detoxifies

red marrow produces RBCs, WBCs, platelets

synthetic functions of skeletal system

long, short, flat, irregular, sesamoid, sutural, pneumatized

what are the seven main bone shapes

longer than they are wide

long bones

compact and spongy bone tissue

what are long bones made of

humerus, radius, ulna, femur, tibia, fibula

long bones examples

equal in length and width

short bones

compact external and spongy internal

structure of short bones

carpals and tarsals

short bones examples

thin and flat

flat bones

2 plates of compact that encapsulate spongy center

flat bone structure

protection, surface area for muscle attachment

flat bone function

skull, thoracic cage, pelvis

flat bones examples

odd/complex shape

irregular bones

vertebrae, hyoid bone, sphenoid bone, mandible, ethmoid bone

irregular bone examples

located within tendons

sesamoid bones

protect tendons, improve mechanics of joint

sesamoid bone function

patella

sesamoid bone example

small, flat, odd shaped bones of skull in suture line

sutural bones

location

how are sutural bones classified

flat bone

what are sutural bones also regarded as

jointed areas where flat bones come together

suture

hollow/contain pockets

pneumatized bones

ethmoid

pneumatized bones examples

thin layer of hyaline cartilage covering articular sites

articular cartilage

dense irregular collagenous connective tissue that covers bone surface

periosteum

blood vessels, nerves osteoprogenitor cells, osteoblasts

what is found in periosteum

perforating fiber

what helps attach periosteum

remodeling, growth, fracture repair

periosteum function

covers most internal surface of bone

endosteoum

osteoprogenitor cells, osteoblasts, osteoclasts

what is found in endosteoum

remodeling, growth, fracture repair

endosteoum function

hard, dense outer region

compact bone

resist linear compression and twisting force

compact bone function

honeycomb framework

spongy bone

resist force from many directions, provides cavity for red bone marrow

spongy bone function

separates proximal and distal epiphyses from diaphysis

epiphyseal lines

line of hyaline cartilage in developing bones

epiphyseal plates

loose connective tissue that supports blood forming hematopoietic cells

red bone marrow

decreases

what happens to red bone marrow throughout life

pelvis, proximal femur, humerus, vertebrae, ribs, sternum, clavicle, scapula, skull

where is red bone marrow found

triglycerides, blood vessels, adipocytes

what makes up yellow bone marrow

endosteum and periosteum

which areas produce more stem cells/osteoblasts

bone forming cells, synthesize and secrete collagen fibers and matrix material

osteoblast

send out seeds of calcium phosphate to matrix

how do osteoblasts initiate calcification

become trapped in calcified matrix secretion

how does osteoblasts become osteocytes

break down collagen fibers and minerals in matrix, bone reabsorbing

osteoclast

secrete HCL and lysozymes

how do osteoclast breakdown bones

hole where blood vessels and nerves reside

central canal

lacunae

where do osteocytes reside

cavities in lamellae filled with interstitial fluid

lacunae

passageways that connect lacunae

canaliculi

share resources and communication

purpose of canaliculi

bone formation

ossification/osteogenesis

embryological/fetal development, before adulthood, remodel as adult, healing fractures

when do bones form

built on membrane of embryonic connective tissue

intramembranous ossification

built on hyaline cartilage

endochondral ossification

mesenchyme

what does intramembranous ossification develop from

embryonic tissue that develops into connective and skeletal tissues

mesenchyme

skull, facial bones, mandible, diaphysis of clavicle

what types of bones are formed from intramembranous ossification

middle part

diaphysis

second month of development

when does endochondral ossification occur

primary ossification center

where does endochondral ossification formation occur

activity of epiphyseal plate

how do bones increase in legnth

bones growing thicker

appositional growth

between periosteum and bone surface

where are osteoblasts found

calcium, weight bearing exercise

how to have stronger bones

gravity

what keeps bones dense

reactive, reparative fibrocartilaginous, reparative bony, remodeling

steps in bone repair

inflammation via hematoma

reactive phase

formation of fibrocartilaginous callus

reparative phase part 1

formation of bony callus

reparative phase part 2

bony callus remodeled

remodeling phase

open, closed, comminuted, greenstick, impacted, potts, colles, stress

what are the types of fractures

broken ends break through skin

open fracture

does not break skin

closed fracture

splintered, crushed, broken into pieces

comminuted fracture

one side is broken and other side is bent

greenstick fracture

one end is driven into the other

impacted fracture

fibula fracture with injured tibial articulation

pott’s fracture

radius fracture where distal fragment is displaced

colles fracture

microscopic fissures

stress fracture

breakdown by osteoclasts matches bone formation by osteoblasts

bone remodeling

slows bone loss by inducing apoptosis of osteoclasts via estrogen

how does sex steroid affect bone growth

calcium, phosphorus, fluoride, magnesium, iron, maganese

which elements promote bone growth

collagen synthesis

vitamin c bone growth

stimulates osteoblast activity

vitamin a bone growth

synthesize bone proteins

vitamin k and b12 bone growth

increase absorption of calcium from food in GI tract

vitamin d bone growth

growth spurt, widens pelvis

estrogen/testosterone bone growth