Introduction to Osteology Flashcards
What is osteology?
Osteology is the study of bones.
What is the bone matrix made of?
Inorganic salts like calcium phosphate & calcium carbonate, and collagen fibers.
What is calcification or mineralization?
Deposition of salts like calcium phosphate and calcium carbonate in the framework of collagen fibers
What is the function of mineral salts and collagen fibers?
Mineral salts confer hardness of bone
Collagen fibers give bone great tensile strength
How many bones does an adult skeletal system consist of? What is each bone called?
206, organ
What are the two parts of the skeletal system?
Axial and appendicular
How many bones does the axial skeleton consist of?
80
What are the parts of the axial skeleton?
Skull, auditory ossicles, hyoid bone, vertebral column, thoracic cage
How many bones does the appendicular skeleton consist of?
126
What are the parts of the appendicular skeleton?
Shoulder girdle, Upper limb, Pelvic girdle, Lower limb
What is the function of axial skeleton?
Protects the organs of the head, neck and trunk
What is the function of appendicular skeleton?
Anchors the appendages to the axial skeleton
What are the functions of the bone?
Support: supports the body. Eg: pelvis
Levers for muscles: muscles are attached to bones. when muscles contract, bones act as levers to allow movement. Eg: humerus
Protection of organs: bones like ribs and skull protect heart, lungs and brain
Production of blood cells: RBC, WBC and platelets are produced in the red marrow of bone.
Storehouse for calcium and phosphorus: calcium and phosphate ions can be released or stored in bones to maintain constant concentration of these ions in body fluids.
What are the two types of stem cells in bone marrow?
Hemopoeitic: which produce blood cells
Stromal: which produce fat, cartilage and bone
What are the two types of bone marrow?
Red marrow: most wbc, rbc and platelets arise here
Yellow marrow: some wbc arise here
What happens to yellow marrow in cases of severe blood loss?
The body converts yellow marrow to red marrow to increase blood production.
What is the compact bone made of?
Cortical tissues
What is the spongy bone made of?
Cancellous tissues
Where is spongy bone located?
Inner cavity of bone
What is the functional unit of spongy bone called?
Trabeculae
Where is the compact bone located?
Outer covering of bones
What is the functional unit of compact bone called?
Osteons
What are epiphyseal plates? What is their function?
Plates of cartilage, known as growth plates since they allow growth of bones in length in childhood
What are the six categories of bones according to individual shape?
Long (humerus), flat (cranium), sutural (cranial sutures), irregular (facial), short (tarsus and carpus), sesamoid (patella)
What is the function of flat bones?
Protect internal organs
What is the function of long bones?
Support weight and facilitate movement
What is the shape of short bones?
Cube shaped
Which bones have complex shapes?
Irregular bones
What is the function of sesamoid bones?
Protect tendons from stress and wear
What are bone surface marking?
Distinct features seen on a bone
Where do bone markings occur?
wherever fibrous tissue or muscle is attached to bone
what are the types of markings?
elevation, facets, depressions
What are the types of elevations?
Linear elevations: line, ridge, crest
Rounded elevation: tubercle, tuberosity, malleolus, trochanter
Sharp elevation: spine, styloid process
What is the function of periosteal arteries?
supply blood to periosteum and compact bone
What is the function of epiphyseal veins?
Carry blood away from bones
What is heterotropic ossification?
Process by which bone tissue forms outside of the skeleton usually in the soft tissue
What is the cause of heterotropic ossification?
surgery or trauma to hips and legs
What is an example of heterotropic ossification?
Horse riders develop heterotropic bones in their thighs or buttocks due to chronic muscle strain resulting in small hemorrhagic areas that undergo calcification. This is called rider’s bones and eventual ossification.
