anatomy

axial skeleton

made up of 80 bones protecting essential organs

appendicular skeleton

bones of upper and lower extremities, critical for movement and engagement with the environment

bones

hard tissue made of water, minerals, salts, and protein fibers

cartilage

soft tissue providing structure and protection

ligaments

connective tissue supporting bone connections

joints

connections between bones that form articulations (hinged movement)

haemopoiesis

the process in which red blood cells, white blood cells, and platelets are created in red bone marrow

contractability

the ability to get shorter

extensibility

the ability to lengthen

elasticity

the ability to go back to resting length

excitability

the ability to be stimulated by nervous tissue

atrophy

decrease in the number of myofibrils, or reduce the size of muscles

hypertrophy

increase in the number of myofibrils, or increase the size of muscles

irregular bones

• specialized shape and function

• often meant for protection

• ex. skull

long bones

• long cylindrical shaft enlarged at both ends

• length greater than width

• important for movement

• ex. femur

short bones

• small and cube-shaped

• generally articulate with more than one other bone

• common in wrists and ankles

• ex. carpals

flat bones

• curved surface - thick or thin

• provide protection to the body and have a larger surface area for muscle attachment

• ex. sternum

periosteum

• area of bone not covered by cartilage but instead by a thin shiny white membrane

• forms outer layer/lining of the bone and is important for bone growth, repair, nutrition, and attachment of ligaments and tendons

diaphysis

• shaft/midsection of the long bone consisting of mostly compact, hard bone with few spaces

• compact bone is relatively hard and solid

• found in outer layer of most types of bones

epiphysis

• made up of cancellous/spongy bone

• irregular latticework structure with many spaces (honeycomb)

• also found in short, flat, and irregular bones

• stores red bone marrow and produces blood cells

articular cartilage

• thin layer covering ends of the bone where they articulate with other bones to form joints

• reduces friction between bones and absorbs shock

• some red marrow and blood cell production here

medullary (marrow) cavity

• space within the diaphysis where yellow bone marrow is stored

• marrow stores fat energy production and fat cells

• small opening in the diaphysis called nutrient foramen

• blood vessels pass through here to enter the medullary cavity and provide the marrow and compact bone with blood and nutrients