RAD ANA 3-A Flashcards
adult skeletal system is composed of how many bones
206
These bones and cartilages are united by
ligaments
includes all bones that lie on or near the central axis of the body
axial skeleton
The adult axial skeleton consists of 80 bones and includes the
skull, vertebral column, ribs, and sternum.
This division consists of all bones of the upper and lower limbs (extremities) and the shoulder and pelvic girdles.
Appendicular Skeleton
adult appendicular skeleton comprises ___separate bones
126
is a special type of small, oval-shaped bone that is embedded in certain tendons (most often near joints).
sesamoid bone
the largest sesamoid bones.
two patellae
The other most common sesamoid bones are located in
the posterior foot at the base of the first toe.
consist of a body and two ends or extremities
Long bones
A. Classification of Bones
long, short, irregular, and flat bones
Long bones are found only in the
appendicular skeleton.
roughly cuboidal and are found only in the wrists and ankles.
Short bones
Short bones consist mainly of
Short bones consist mainly of cancellous tissue
consist of two plates of compact bone with cancellous bone and marrow between them.
Flat bones
example of falt bones
calvaria, sternum, ribs, and scapulae
the narrow space between the inner and the outer table of flat bones within the cranium.
Diploe
have peculiar shapes. (
Irregular bones
give examples of irregular bones
vertebrae, facial bones, bones of the base of the cranium, and bones of the pelvis)
usually provide movement in a single direction.
bicondylar
Bicondylar joints are formed by
two convex condyles,
allows the greatest freedom of motion
Ball and socket
true or false:The greater the depth of the socket, the more limited is the movement.
true
positioned opposite each other.
saddle
positioned opposite each other.
saddle
occurs primarily in one plane and is combined with a slight degree of rotation at an axis at right angles to the primary plane of movement.
Condylar
condylar movements
flexion, extension, abduction, and adduction
joint allows rotational movement around a single axis.
Pivot
permit flexion and extension movements only.
hinge
permits the least movement
gliding
implies, is a sliding or gliding motion between the articulating surfaces
gliding
freely movable joints, most often found in the upper and lower limbs
synovial joint
synovial joint is characterized by a fibrous capsule that contains
synovial fluid
also lack a joint cavity, and the articulating bones are held together tightly by cartilage.
Cartilaginous joint
lack a joint cavity. The adjoining bones, which are nearly in direct contact with each other, are held together by fibrous connective tissue.
Fibrous joint
funcitonal classification of joints
a. Synarthrosis —immovable joint
b. Amphiarthrosis —joint with limited movement
c. Diarthrosis —freely movable joint
where is rbc produced
in flat and irregular bones such as the sternum, ribs, vertebrae, and pelvis as well as the ends of the long bones.
Two types of bone formation
intramembranous
endochondral
When bone replaces membranes, the ossification is called
intramembranous.
When bone replaces cartilage, the result is
endochondral
much slower than intramembranous ossification, occurs in most parts of the skeleton, especially in the long bones.
Endochondral ossification
occurs rapidly and takes place in bones that are needed for protection,
Intramembranous ossification
the first center of ossification,
primary center
where does primary effect occurs
midbody area
primary center of ossification in growing bones is called
diaphysis
– appear near the ends of the limbs of long bones.
Secondary center
Most _____ centers appear after birth, whereas most _____ centers appear before birth
secondary, primary
secondary center of ossification is called an
epiphysis
types(?) of Fibrous joints
a. Syndesmosis – slightly movable
b. Suture – immovable
c. Gomphosis – very limited movement
types(?) of Cartilaginous joints
symphysis and synchondrosis
The process by which bones form within the body is known as
ossification.
Ossification begins at about the ____ embryonic week
sixth
