the skeletal system consists of:
bones, joints, cartilage, and ligaments
how many bones does the skeletal system consist of
206
long bones
longer than they are wide
short bones
shaped liked cubes and are found primarily in the arms and legs
flat bone
thin, flat, curved. from the ribs, breastbone and skull
medical term used for bone
osseous tissue
osteocytes
bone cells
two types of bone
- compact bone- dense hard bone
- spongy bone- (aka- cancellous bone) less dense
osteon or haversion system
microscopic unit of compact bone
does not have a haversion canal
spongy bone
found at the end of long bones
epiphysis
in the middle of long bones
diaphysis
articulation
where two bones meet
medullary cavity
the inside is lined with connective tissue Called the endosteum
epiphyseal disc
between the epiphysis and the diaphysis in a growing bone
periosteum
tough, fibrous, connective tissue membrane that covers the outside of the diaphysis
articular cartilage
found on the outer surface of the epiphysis forms smooth shiny surface that decreases friction within a joint
ossification
the formation of bone
two types of bone growth
longitudinally- determines the height of an individual
thicker and wider- to support the weight of the adult
longitudinal growth
generally ceases after puberty
bone resoption
widens the bone, moves calcium from the bone to the blood
condyle
large rounded knob that usually articulates with another bone
head
an enlarged and rounded end of a bone
when someone breaks a hip, its typically what bone
the femoral neck
facet
a small flattened surface
trachantor
a large (tuberosity) found only on the femur
foramen
an opening through a bone
meatus
a tunnel or tubelike passageway
sinus
cavity or hallow space
skeletal system is divided into two sections
- axial skeleton
- appendicular Skeleton
foramen magnem
large hole in the occipital bone
mandible
lower jaw bone, carries the lower teeth
-forms the only freely moveable joint in the skull
maxilla
carries the upper teeth
- an extension of the maxilla is the palatine process
sinuses
air filled cavities located in several bones of the skull
four sinuses
- frontal sinus
- ethmoid sinus
- sphenoidal sinus
- maxillary sinus
hyoid bone
u shaped bone located in the upper neck
vertebra prominens-c-7
used as a landmark in assessing surface anatomy
the sacrum
forms the posterior wall of the pelvis
atlas-C1
- first cervical vertebrae
- supports the skull and allows you to nod "yes"
atlas-C2
allows you to rotate you're head from side to side to say "no"
vertebral foremen
opening for the spinal cord
the thoracic cage
the boney, cone-shaped, cage that surrounds and protects the lungs, heart, large blood vessels, liver and spleen
composed of: sternum- ribs- thoracic vertebrae
the sternum is located where
along the midline of the anterior chest
has three parts- manubrium, body, xiphoid process (tip of sternum)
ribs
- 12 pairs
- posteriorly, twelve pairs of ribs attached to the thoracic vertabrae
- anteriorly, the top seven pairs of ribs attach directly to the sternum by costal cartilage
- these are true ribs
clavicle
looks like a long, slender, S-shaped rod
Glenoid cavity
allows you to rotate your shoulder
- great flexability
upper limbs contain
- humerus (bones of the upper arm)
- the forearm (ulna and radius)
- the hand (carpals, metacarpals and phalanges)
humerus
long bone of the upper arm
radius
one of two bones of the foreman
ulna
second bone of the forearm
supination
palm up-two bones are parallel
pronation
palm down-the bones cross to achieve this movement
the wrist contains
eight carpal bones, which are tightly bound by ligaments
coxal bone
hip bone
-composed of three parts:
(1) ilium
(2)ischium
(3) pubis
the three bones to form ____
the acetabulum, it receives the head of the femur and enables the thigh to rotate
ilium
largest part of the coal bone, can be felt at the hip
- connect in the back with the sacrum, forming the sacoiliac joint
ischium
most inferior part of the coal bone
(you sit)
pubis
most anterior part of the coal bone
obturator foramen
large hole formed as the pubic bone fuses with a part of the ischium
the most common site of fracture in the elderly who break hips
the neck of the femur
patella
kneecap
tibia and fibula
form the leg
tibia-the thick inner bone (TIB)
fibula-lateral to the tibia (LA- lateral)
three types of muscle
- skeletal
- smooth
- cardiac
skeletal muscle
voluntary muscle is controlled by choice
functions of the skeletal muscle
- functions
- produce movement
- maintain body posture
- stabilize joints
- produce heat- helps to maintain body temp
smooth muscle
visceral muscle happens involuntarily
cardiac muscle
food only in the heart
fascia
layers of tough connective tissue that surround large skeletal muscle
tendon
strong cordlike structure that extends toward and attaches to the bone
sliding filament theory
the interaction of actin and myosin sliding past each other causing the muscles to contract
ATP and calcium
play an important role in the contraction and relaxation of muscles
recruitment
the process of recruiting additional fibers to achieve a greater muscle force
prime mover
"chief muscle"
synergists
"Helper muscle"
antagonists
muscles that oppose the action of other muscles
hypertrophy
overuse of a muscle
atrophy
wasting away or decrease in the size of a muscle
how muscles are named
- size origins
- shape
- direction of fibers
- location
- number of
- origin and insertion
- muscle action
medical word for chewing
muscles of mastication
sternocleidomastoid
causes the head to rotate toward the opposite direction
trapezius
origin is at the base of the occipital bone in the skull and to the spine of the upper vertebral column
intercostal muscles
located between the ribs and are responsible for raising and lowering the rib c
diaphragm
chief muscle of inhalation
muscles that form the abdominal wall
the arrangement enables the muscles to contain, support, and protect abdominal organs
the deltoid
abducts the arm
-it is common but not always the best
triceps brachii
lies along the posterior surface of the humerus
-back of arm
aka boxers muscle
where are biceps found ?
- arms and legs
biceps brachii
located along the anterior surface to the humerus
the muscles are generally located along the ____
forearms
gluteal muscles
- gluteus maximus
- gluteus medius
- gluteus minimus
gluteus maximus
largest muscle in the body
vastas laterals
used as an IM injection site
all muscles extend from the
ischium to the tibia
tibialis anterior
dorsiflexion of the foot
gastrocnemius and soleus
major muscles on the posterior surface of the leg and form the calf of the leg