Long Bone Anatomy

proximal/distal epiphysis description

knobby ends of bone

proximal/distal epiphysis composition

composed mostly of spongy bone

proximal/distal epiphysis contents

red bone marrow

endosteum

lining of medullary cavity

yellow marrow contents

adipocytes

yellow marrow function

storage of fat cells

diaphysis description

the shaft of the bone

diaphysis content

contains medullary cavity

articular cartilage description

thin sheet of HYALINE cartilage that covers the epiphysis

articular cartilage function

reduces friction as bones move

spongy bone (aka cancellous)

porous, filled with red bone marrow

epiphyseal (growth) plate

in both proximal and distal epiphysis

red marrow

makes red blood cells (hematopoiesis)

medullary cavity - infants

contains red bone marrow

medullary cavity - adults

contains yellow marrow (fat/energy storage)

compact bone

dense, hard outer layer of bone

nutrient foramen

small hole for blood vessels to enter/exit, helps cells stay alive

periosteum

fibrous, outside covering of the diaphysis, vascular and rich with nerves