22-23 skeletal system

axial skeleton

Portion of the skeletal system that consists of the skull, rib cage, and vertebral column

appendicular skeleton

The portion of the skeleton that attaches to the axial skeleton and has the limbs attached to it

compact bone

Hard, dense bone tissue that is beneath the outer membrane of a bone

spongy bone

Layer of bone tissue that has many small spaces and is found just inside the layer of compact bone.

long bones

bones that are longer than they are wide; provide structure and mobility

short bones

cube shaped bones of the wrist and ankle

flat bones

These bones are thin, flat, and curved. They form the ribs, breastbone, and skull.

irregular bones

bones of the vertebrae and face

Periosteum

a dense layer of vascular connective tissue covering the bones except at the surfaces of the joints.

diaphysis

tubular shaft that runs between the proximal and distal ends of a long bone

Epiphysis

End of a long bone

yellow marrow

found in the medullary cavity of long bones; stores fat

medullary cavity

cavity within the shaft of the long bones filled with bone marrow

red marrow

produces red blood cells

bone markings

reveal where muscles, tendons, and ligaments were attached and where blood vessels and nerves passed

Osteoblasts

Bone building cells

osteoclasts

Bone destroying cells

bone remodeling

ongoing replacement of old bone tissue by new bone tissue

fractures

a crack or break in a bone

hematoma

a solid swelling of clotted blood within the tissues

vertebral column

A series of irregularly shaped bones called vertebrae

cervical, thoracic, lumbar, sacral, coccyx

cervical

neck region

thoracic

chest region

lumbar

area of back between ribs and hips

sacrum

bone formed from five vertebrae fused together near the base of the spinal column

coccyx

tailbone

interverbral discs

stacked one above another and provide cushioning to the backbone

joints

Areas where two or more bones join together

fibrous joints

consists of inflexible layers of dense connective tissue, holds the bones tightly together

cartilaginous joints

allow only slight movement; consist of bones connected entirely by cartilage

synovial joints

freely movable joints

ligaments

Connect bone to bone

dislocation

displacement of a bone from its joint

arthritis

joint inflammation

Osteoperosis

a condition in which the bones become fragile and break easily

structure of a long bone

periosteum- outer layer of long bone

compact bone- hard and dense material on walls of diaphysis below periosteum

epiphysis- ends of long bone; narrower end has growth plate (or epiphyseal line if older)

diaphysis- tubular shaft that runs through the proximal and distal ends of bone

medullary cavity- hollow region of diaphysis filled with yellow bone marrow

functions of a long bone

skeletal system provides support for organs

skeletal system provides protection for all organs

brain, lungs

skeletal system allows movement

muscles use bones like levers; tendons attach muscles to bones

cartilage

flexible connective tissue; between bones, ears, nose ribs, sternum

ligaments

bone to bone

tendon

muscle to bone

calcium

needed for nerve transmission and muscle contraction; carried through the body by blood

high calcium

causes kidney stones

bone remodeling (high calcium)

calcium homeostasis; osteoblasts take calcium and paste it onto bones

PTH (low calcium)

parathyroid gland releases osteoclasts that eat away at bone matrix and releases calcium into blood

spinal curvatures

scoliosis, kyphosis, lordosis

scoliosis

“s” shaped spine; usually fixed non-surgically

kyphosis

exaggerated outward rounding of the thoracic vertebrae

lordosis

curvature of the lumbar vertebrae