AP chapter 6 bones

5 primary functions of the skeletal system

support, storage of minerals and lipids, blood cell production, protection, leverage

Sutural bones

Wormian bones, are small, flat, irregularly shaped bones between the flat bones of the skull

Irregular bones

have complex shapes with short, flat, notched, or ridged surfaces. The vertebrae that form the spinal column, the bones of the pelvis, and several bones in the skull are examples of irregular bone

short bones

are boxlike in appearance. carpal bones (wrists0 and tarsal bones (ankles)

flat bones

have thin parallel surfaces which produce a flattened shape. flat bones form the roof of the skull, the sternum, the ribs and scapulae)shoulder blades. parietal bone

long bones

relatively long and slender. they are located in the arm, forearm, thigh, and leg, palms ETC humerus

sesamoid bones

usually small, round, and flat, they develop inside tendons and are most often encountered near joints at the knee, hands, and feet. patella

bone markings

depressions or grooves along the bone surface. elevations or projections. tunnels where blood and nerves enter bone

diaphysis

the shaft of a long bone, heavy wall of compact bone, or dense bone

epiphysis

the head of a long bone. wide part at each end, mostly spongy bone covered with compact bone(cortex)

metaphysis

The region of a long bone between the epiphysis and diaphysis, corresponding to the location of the epiphyseal cartilage of the developing bone.

bone tissue

dense, supportive connective tissue, contains specialized cells, produces solid matrix of calcium salt deposits

medullary cavity

Compact bone forms a sturdy protective layer that surrounds a central space called the

trabecular

spongy bone is also called

canaliculi

passageways for blood vessels through the matrix, extend between the lacunae and nearby blood vessels, which osteocytes exchange nutrients, wastes, and gases.

matrix

contains bone cells, or osteocytes  , within pockets called lacunae

periosteum

covers outer surfaces of bones. consists of outer fibrous and inner cellular layers.

calcium phosphate

2/3 of bone matrix is

osteogenic, osteoblasts, osteocytes

Which three types of bone cells are developmentally related and what is their progression from the earliest to the latest stage?

osteocytes

maintain the bone matrix. are mature bone cells that make up most of the cell population. don’t divide. are arranged in the concentric lamellae

osteoblasts

bone formation cell. immature bone cell that produce new bone matrix in a process called osteogenesis. A cell that produces the fibers and matrix of bone.

osteoid

matrix produced by osteoblasts, but not yet calcified to form bone

Osteogenic Cells

stem cells that divide to produce osteoblasts

osteoclasts

are cells that absorb and remove bone matrix. Secrete acids and protein-digesting enzymes

osteon

basic functional unit of mature compact bone

Haversian system

another name for osteons

central canal

In an osteon, the osteocytes are arranged in concentric layers around a vascular. haversian canal

haversian canal

another name for central canal

perforating canal

Volkmann’s canals. other passageways, extend perpendicular to the surface. Carry blood vessels into bone and marrow

circumferential lamellae

lamellae wrapped around the long bone. are found at the outer and inner surfaces of the bone, where they are covered by the periosteum and endosteum, respectively

concentric lamellae

create a target-like pattern, with the central canal as the bull’s-eye.

interstitial lamellae

fill in the spaces between the osteons in compact bone.

trabeculae

The matrix in spongy bone forms a meshwork of supporting bundles of fibers called

red bone marrow

between trabeculae. has blood vessels. forms red blood cells and supplies nutrients to osteocytes

yellow bone marrow

it stores fat. adipose tissue important as an energy reserve.

periosteum

on the outside. Covers all bones except parts enclosed in joint

capsules. Made up of an outer, fibrous layer and an inner,

cellular layer. participates in bone growth and repair

perforating fibers

collagen fibers of the periosteum

endosteum

on the inside. and incomplete cellular layer. covers trabeculae of spongy bone. is an active bone growth and repair

osteogenesis

bone formation

ossification

the process of replacing other tissues with bone

calcification

the process of depositing calcium salts. occurs during bone ossification and in other tissues

Endochondral Ossification

Ossifies bones that originate as hyaline cartilage. Most bones originate as hyaline cartilage. There are seven main steps

appositional growth

Compact bone thickens and strengthens long

bone with layers of circumferential lamellae

Intramembranous Ossification

Also called dermal ossification because it occurs in the dermis. Produces dermal bones such as mandible (lower jaw) and clavicle (collarbone). 5 main steps