skeletal system Flashcards
what is the axial skeleton?
axial is, the bones that from the longitudinal axis of the body.
the bones in the vertebral column
7 cervical vertebrae
12 thoracic vertebrae
5 lumbar vertebrae
Sacrum: 5 fused
Coccyx: 4 fused
where are the cervical vertebrae located?
in the neck
what are the two first vertebrae?
C1 (atlas)
C2 (axis)
describe the thoracic vertebrae
Articulate with ribs
Larger than cervical vertebrae
Long spinous process that hooks sharply downward
describe lumbar vertebrae
Much larger than other vertebrae to support the weight of the upper body
describe the bony thoracic or rib cage
12 pairs of ribs articulate with the 12 thoracic vertebrae posteriorly
True ribs,1-7 pairs, articulate anteriorly directly to the sternum by cartilage
False ribs, pairs 8-12, articulate indirectly or not at all
The last 2 pair do not connect at all and are called floating ribs.
the three parts of the sternum
Manubrium
body
Xiphoid process
all the bones of the skull 7
lobes(frontal, partial, temporal, occipital)
mandible
maxilla
sphenoid
lacrimal
ethmoid
zygomatic
what bone in the skull is movable?
mandible
auditory ossicles(ear bones)
Malleus
Incus
Stapes
what is the appendicular skeleton
the limbs and the girdles which attach the limbs to the axial skeleton
what is the pectoral girdle
the clavicle and the scapula
what are the arm bones?
humerus(upper arm)
radius(lower arm, elbow to thumb side of wrist)
ulna(lower arm, elbow to pinkie side of wrist)
bones in the hand
phalanges
metacarpals
carpals
what is the pelvic girdle?
two hip bones.
Each hip bone is formed from the fusion of 3 bones:
Ilium
Ischium
Pubis
what are all the coxal bones
sacrum
ilium
pubis
ischium
pubic symphisis
the leg bones
femur(thigh bone)
patella(knee bone)
tibia(large bone in lower leg)
fibula(smaller bone in lower leg)
bones of the foot
phalanges
metatarsals
tarsals
what are the shapes of bones? 5
long bones- longer than they are wide, provides structure. femur
short bones- usually cube shaped, they allow multidirectional movement. tarsals
flat bones- larger surfaces for muscle attachment, provides protection for soft tissue. cranial bones
irregular bones- complicated shapes, provides support. vertebrae column
sesamoid bones- form with tendons, protects from friction and relieves muscle/tendon tension.
the two types of bones
compact- dense, looks smooth, surrounds spongy bone
spongy- made up of lots of small bone pieces, lots of open space, at the end of long bones
where is red marrow found?
spongy bone
what is hematopoiesis.
hematopoiesis is the formation of blood cells
yellow marrow
found in medullary cavity and it store fat, calcium, minerals and phosphorus.
how does the skeleton provide support?
it provides support because it is an internal frame that supports and anchors all the soft organs.
how does the skeleton provide protection
provides some protection to soft body organs
how does the skeleton provide movement?
it provides movement by the skeletal muscles attaching by tendons and the tendons use bones as levers to move body parts.
what are fontanels
Spaces between bones of the skull in an infant
Commonly called soft spots
Fully ossified by 2 years
Allows for growth of the brain and skull
what is ossification?
Ossification is the formation of bone from cartilage
At birth, bones are part cartilage and part bone
The skeleton is fully ossified by age 2 except for growth plates
when are growth plates fully ossified?
growth plates are fully ossified by the end of adolescence
what are osteoblasts and osteoclasts?
-osteoblasts are bone forming cells that mature into osteocytes.
-osteoclasts are large cells that break down bone and release calcium ions into the blood.
what is osteoporosis?
osteoporosis is weakening of the bones that happens with aging, and causes tissue loss in the bone.
what is a hip fracture?
a hip fracture is actually a fracture at the proximal end of the femur near the hip.
what are joints?
joints are where two bones meet, and it holds the bones together but also gives mobility
what are the three joint types?
fibrous, no movement. skull
cartilaginous, slightly moveable. vertebrae
synovial, bones separated by a cavity filled with synovial fluid, the most movement.
what are the 4 parts of synovial joints?
- articular cartilage- like a layer of cartilage over the head of the bone.
- fibrous articular capsule- an outer layer around the membrane and synovial fluid and it touches both bones
- the joint cavity- the cavity contains the synovial fluid and the fluid fills the space between the two bones
- this is all reinforced by ligaments
types of synovial joints
ball and socket joints- most moveable, found in the hip and shoulder
pivot joints- allow rotary movement on a single axis, A cylinder shaped bone rotates inside a ligament that forms a ring around the bone. like the radius and ulna
hinge joint- Allows movement back and forth on one plane. Made up of two or more bones covered with cartilage and lubricated with synovial fluid. like the elbow
what is cartilage?
it is a firm tissue that is softer and more flexible then bone, its often found between bones, it cushions the bones and enhances their flexibility and resiliency.
what are ligaments?
ligaments connect bone to bone, they also help stabilize joints by preventing twisting or dislocation.
what are tendons?
tendons attach muscle to bone, they move our joints when they contract.
the Achilles tendon is the strongest and it attaches the calf muscle to the heel.
tendon tears take a long time to heel cause they have lower blood supply than muscle.
