Structure of Long Bone

shaft

diaphysis, found on long axis, consists of mostly compact bone

what covers the diaphysis?

periosteum

periosteum

fibrous membrane covering that surrounds long bone, made of dense irregular connective tissue

what penetrates the bone?

perforating fibers

perforating (Sharpey’s) fibers

collagen fibers continuous with tendons, ligaments that penetrate the bone

osteons

organizational unit of compact bone

lamellae

layers of bone matrix that form osteons

epiphyses

ends of long bone, encloses a layer of spongy bone

proximal epiphysis of femur

forms the head

spongy bone

composed of passgeways of trabeculae, with lots of space

what do the outer surface of epiphyses contain?

articular cartilage

function of articular cartilage

absorb shock and reduce friction during movement

epiphyseal plate

composed of hyaline cartilage, growth plate

in adulthood, the epiphyseal plate becomes the ________

epiphyseal line

hollow portion of the middle of the shaft

medullary cavity

function of periosteum

blood vessels and nerves travel through it and invade the bone

medullary cavity

aka central cavity, hollow portion of shaft, lined with spongy bone

in adults the medullary cavity is filled with

yellow marrow, consists of mostly of adipose tissue

in children, the medullary cavity is filled most with

red marrow - produces red blood cells

in both adults and children, red bone marrow is found _______

in between the trabeculae

in adults, the trabeculae also store _______

adipose tissue

membrane that covers the trabeculae

endosteum

The hardness of bone is due to the _________ deposited in its ___________.

inorganic calcium salts, ground matrix

The flexibility of the bone comes from the _________ of the matrix, particularly the ________.

organic elements, collagen fibers

osteoblasts

bone forming cells

where are osteoblasts found?

in the periosteum

osteoclasts

bone destroying cells

where are the osteoclasts found?

in the endosteum

endosteum

inner surface lining of diaphysis

central haversian canal

runs parallel to long axis of bone, runs through center of osteon, carries blood vessels, lymph, and nerves

osteocytes

mature bone cells

where are osteocytes found?

in the lacunael

lacunae

chambers arranged in lamellae

osteon is also known as

haversian system

what does an osteon consist of?

central canal and all concentric lamallae

canaliculi

tiny canals radiating from central canal, communication and transport network for nutrients

volksmann’s canals 

perpendicular to shaft, come from periosteum, extend to bone marrow cavity, connect central cavities to each other