Musculoskeletal System PT1 Flashcards
What are the two distinct categories the bones of the skeleton are divided into?
Axial Skeleton:
Provides main area of support for body & includes cranium, vertebral column & rib cage
Appendicular Skeleton:
Consists of appendages or bones of limbs, together with girdles joining axial skeleton
What are the functions of the Skeletal system?
SUPPORT - Rigid framework to body, giving it shape & providing suitable sites for attachment of skeletal muscle
PROTECTION - Protection for internal organs
MOVEMENT - Large surface area for attachment of muscles. Long bones provide system of levers pulled out by other muscles
BLOOD PROTECTION - Within bones, bone marrow produces both RBCs & WBCs. RBCs produced at end of long bones such as humerus & femur & in some flat bones such as pelvis & sternum. WBCs usually produced in shafts of long bones
MINERAL STORAGE - Bones have storage for vital minerals like calcium & phosphorus, distributed to other parts of body when needed
Outline long bones
Cylindrical shape & found in limbs of body
E.g. Femur, tibia, humerus, phalanges
Primary function is act as levers & thus essential in movement
Secondary function is production of blood cells occurring deep inside bone
Outline flat bones
Offer protection to internal organs
E.g. sternum, ribs, bones of cranium & pelvis
Provide suitable sites for muscle attachment, with origins of muscles attaching to them
Thus, muscles contracting has firm immovable base to pull against, thus carrying out function effectively
Outline irregular bones
Named due to complex, individual shapes & difficulty classifying them
They’ve variety of functions including protection, e.g.:
Vertebrae protects spine & helps shock absorption when running & jumping
Bones of face
Outline sesamoid bones
Have specialised function of easing joint moving & resist friction & compression
Usually developed in tendons & covered with layer of articular cartilage as they exist where bones articulate
Generally small but vary in size
Largest = patella which aids smooth articulation & movement between femur & tibia & prevents knee from hyperextending
Outline short bones
Small & compact, often equal in length & width
Designed for strength & weight bearing
E.g. when performing handstand:
Wrist bones (carpals)
Ankle (tarsals) & calcaneum