the skeletal system

what is the backbone supported by?

muscles and ligaments

what does the red marrow do?

manufactures RBC and WBC

skull

-axial skeleton -cranium -facial bones

sternum

-axial skeleton -manubrium -corpus sterni -xiphoid process

hyoid bone

-axial skeleton -provides an attachment point for the tongue muscles

each muscle is attached to what?

2 bones (the origin and the insertion)

amount of bone marrow adults have?

-1/2 red bone marrow -1/2 yellow bone marrow -all red bone marrow when born

appendicular skeleton

-126 bones -pectoral girdle, pelvic girdle, and appendages

axial skeleton

-80 bones -includes vertebral column, rib cage, sternum, skull and hyoid bone -protects vital organs including brain, heart and lungs

rib cage

-axial skeleton -12 paired ribs -10 pairs of true ribs -2 pair of floating ribs

vertebral column (spine)

-axial skeleton -aka spine -33 vertebrae (cervical vertebrae, thoracic vertebrae, lumbar vertebrae and sacral vertebrae)

ossicles

-axial skeleton -bones in middle ear

upper appendages

-aka arms -humerus (upper arm) -radius (thumb side forearm) -ulna (pinky side forearm) -carpals (wrist) -metacarpals (hand) -phalanges (fingers)

spongy bone

-aka cancellous bone -consists of trabeculae (network of girdles with open spaces filled with red bone marrow) -lightweight and porous

compact bone

-aka cortical bone -consists of tightly packed cells -strong, dense, rigid -haversian canals run vertically through compact bone

lower appendages

-aka legs -femur (thigh) -patella (knee) -fibula (pinky side shin) -tibia (big toe side of shin) -tarsals (ankle) -metatarsals (foot) -phalanges (toes)

diarthrosis joint

-always synovial -free movement -wrist, knee, shoulder

in long bones, the diaphysis consists of...

-compact bone surrounding the marrow cavity -spongy bone containing red bone marrow in the epiphyses

synarthrosis joint

-either fibrous or cartilaginous -immovable -skull, teeth/mandible

amphiarthrosis joint

-either fibrous or cartilaginous -slight range of movement -intervertebral discs, distal tibiofibular joint

cartilaginous joints

-held together by cartilage *synchondrosis: hyaline cartilage, nearly immovable. ex) first rib/sternum *symphysis: fibrocartilage, slightly moveable. ex) intervertebral discs, pubic symphisis

fibrous joints

-held together by fibrous connective tissue *suture: immovable. ex)skull *gomphosis: immovable ex)teeth/mandible *syndesmosis: slightly movable ex) distal tibiofibular joint

types of joints?

-hinge joints -ball and socket joints -pivot joints -ellipsoid joints -gliding joints -saddle joints

origin

-immovable -where joint attaches to bone

synovial joints

-most common type of joint -characterized by a joint cavity filled with synovial fluid *pivot: allows rotation; ex)atlantoaxial joints *hinge: allows movement in one plane; ex)knee *saddle: allows pivoting in 2 planes and axial rotation; ex)first metacarpal/trapezium *gliding: allows sliding; ex)carpals *condyloid: allows pivoting in 2 planes, no axial rotation; ex)radiocarpal joint *ball and socket: highest range of motion; ex)hip

skeletal system has an important role in while body functions?

-movement (action of skeletal muscles on bones move body) -mineral storage (bones serve as storage facilities for essential mineral ions) -support (bones act as framework and support system for organs) -protection (bones surround and protect key organs) -blood cell formation (RBCs are produced in marrow of certain bones)

Haversian system

-provides a reservoir for calcium and phosphorous for the blood -haversian canals (surrounded by concentric circles of bone tissue called lamellae -surrounded by concentric circles of bone tissue called lamellae -spaces between the lamellae are lacunae

functions of the skeletal system?

-providing structural support -providing movement -providing protection -producing blood cells -storing substances (fat, minerals)

pectoral girdle

-scapulae (shoulders) -clavicles (collar bones)

bone classifications

-short -long -flat -irregular

insertion

-the bone that moves as the muscle contracts and relaxes

pelvic girdle

-two pelvic bones (hips); attach to sacrum

how many bones in human skeleton?

206 bones

What does red bone marrow produce?

RBC and WBC

what do bones provide?

attachment point for muscles

how is the skeleton divided?

axial and appendicular skeleton

what does the cranium protect?

brain

what is the outside layer of bones?

compact bone

2 types of connective bone tissue

compact bone and spongy bone

what does the rib cage protect?

heart and lungs

what provides cushion for the backbone?

intervertebral discs

what does the pelvis protect?

reproductive organs

where will you find synovial joints?

shoulders and knees

what does the vertebrae protect?

spinal cord

yellow bone marrow

stores fat

most common joint?

synovial

where are RBCs produced?

the marrow of certain bones

what does the skeletal system provide a reservoir for?

to store the minerals calcium and phosphorous

what are joints?

where two or more bones meet

can synovial joints move?

yes, freely moveable