Skeletal System

heel bone

calcaneus

periosteum

the dense, tough outer shell containing blood vessels and nerves

diaphysis

shaft of a long bone

endosteum

inner lining of a long bone

epiphysis

end of a long bone

epiphyseal plate

cartilage layer where long bones grow in length

cartilage

provides cushions at joints (nose and ears)

ligaments

bones are attached to other bones

tendons

muscles are attached to bones

axial

bones that lie along the center of the body such as vertebral column, rib cage, and skull (80 bones)

appendicular

bones and joints of the appendages (upper & lower limbs, 126 bones)

fontenal

soft spot on a baby’s head

ossification

bone tissue formation

mandible

the only movable bone of the skull

ossicles

the hammer, anvil, and stirrup

stirrup (stapes)

the smallest bone in the body

5 functions of the skeletal system

1. provides shape and support

2. protects internal organs

3. stores minerals and fat

4. produces blood cells and platelets

5. assists in movement

femur

long bones

carpals, tarsals

flat bones

vertebrae

irregular bones

patella

sesamoid bones

osteoblasts

bone-building cells

osteoclasts

break down bone tissue

hematopoiesis

production of red blood cells in bone marrow

projections

bulge from a bone and attach muscles, ligaments, and tendons

openings

holes or spaces in bones

articulation

two or more bones joined at one point

articular

cartilage lines the bony surface of joints

synarthrosis

immovable (sutures of the cranium)

amphiathrosis

slightly movable (bones of the pelvis)

diathrosis

freely movable (bones of the knee/elbow)

ball & socket

full rotation (shoulder/hip)

hinge

one plane (elbow/knee)

sliding/gliding

several bones sliding past each other (wrist/ankle)

pivot

partial rotation (base of skull)

saddle

thumb

adduction

towards the body

abduction

away from the body

flexion

decrease the angle

extension

increase the angle