A&P - Skeletal System and Long Bone Flashcards
Question 1
Functions of the Skeletal System
Movement - the skeleton allows movement of the body as a whole and it’s individual parts. Production of blood cells - certain bones in the skeleton contain red bone marrow which produces red blood cells and platelets e.g. clavicle and sternum
Long bone
Long Bone
Diaphysis
Tubular shaft that runs between the proximal and distal ends of the bone.
Makes up the length of the bone and is cylindrical in shape.
Separated from epiphyses by the epiphyseal line.
Composed of a thick layer of compact bone surrounding the medullary cavity which is filled with yellow marrow.
Long Bone
Epiphysis
Proximal and distal epiphyses are where long bones meet with other bones at joints.
Covered in articular cartilage to allow bones to slide past one another easily.
Filled with spongy bone
Epiphyseal line (adults) / plate (juveniles)
Long Bone
Periosteum
Contains blood vessels, nerves and lymphatic vessels that nourish compact bone.
Tendons and ligaments also attach to the bones.
Covered with articular cartilage, a thin layer of cartilage which reduces friction and acts a shock absorber.
Outer connective tissue
Spongy Bone
Flat bones like the carnium consist of a layer of spongy bone which is lined on either side by a layer of compact bone.
Work together to protect internal organs.
e.g. brain is still protected by the intact inner layer
Inner portion of bone.
Compact Bone
Oiuter part of the bone
Endosteum
Connective tissue lining medullary cavity
Medullary Cavity
Opening in centre of bone
In adults - yellow marrow cavity
Infants - red marrow cavity (filled new forming red blood cells)
Medullary cavity lined with a thin layer of connective tissue called endosteum.
Articular Cartilage
Cartilage at joint surfaces.
Produce smooth articulations among joint surfaces.
Spongy Bone
Lighter and less dense
Highly Vascularised and has red bone marrow
Compact Bone
Closely packed haversian systems
Percentage of Bone
Skeleton
20% spongy
80% compact
