The Skeletal System Flashcards
are longer than they are wide and have knobby ends where the articulations form.
Long bones
shaft or body
Diaphysis
head of each end of a long bone
Epiphysis
marrow cavity or space that
contains yellow marrow
Medullary cavity
are equal in length and width, making them nearly cube-shaped.
Short bones
are thin and provide both protection and surfaces for muscle attachments.
Flat bones
have complex shapes, such as those of the face and vertebral column.
Irregular bones
help from bone by
secreting substances that comprise
the bone’s matrix.
Osteoblasts
dissolve unwanted or
unhealthy bone.
Osteoblasts
are mature osteoblasts
that have become entrapped in the hardened bone matrix.
Osteocytes
Collagen fibers in the matrix make bone highly resistant to stretching resistant to stretching forces
TENSILE STRENGTHS
Calcium salts allow bones to resist strong
squeezing forces
COMPRESSIONAL STRENGTHS
Bone lacks the ability to endure twisting, In fact, most bone fractures result when torsional forces are exerted on an arm or leg.
TORSIONAL STRENGTHS
SKELETAL SYSTEM
206 bones
SKULL
22 BONES
Cranium
8 bones
is the bony structure
housing the brain.
Cranium
forms the forehead, roofs of the eye sockets, and front part of the cranial floor.
Frontal
Frontal
1 bone
form the sides and roof of
the cranium
Parietal
Parietal
2 bones
form the lower side of the cranium and part of the cranial floor.
Temporal
Temporal
2 bones
forms the back part of the
skull and most of the cranial floor.
Occipital
Occipital
1 bone
the middle of the cranial floor and is where all the other cranial bones attach, like the keystone joining two arches to form a doorway.
Sphenoid
Sphenoid
1 bone
forms the anterior part of the cranial floor, the medial part of the eye sockets, and superior portions of the nasal cavity.
Ethmoid
Ethmoid
1 bone
Face
14 bones
form the bridge of the nose.
nasal
nasal
2 bones
form the upper jawbone and join with all the other facial bones except the mandible (lower jawbone)
maxillary
maxillary
2 bones
or cheekbones, form the
cheek prominences and part of the wall of the eye sockets.
Zygomatic
Zygomatic
2 bones
the largest, strongest facial bone
Mandible
Mandible
1 bone
are the smallest, thinnest
bones on the medial eye socket.
lacrimal
lacrimal
2 bones
form the posterior portion of
the hard palate, part of the lower eye sockets, and part of the floor and the sides of the nasal cavity.
palatine
palatine
2 bones
project into the nasal cavity
to filter air before it passes toward the trachea and lungs.
inferior nasal conchae
inferior nasal conchae
2 bones
joins with the maxillae and
the palatine bones to form the floor of the nasal cavity. Along with cartilage and the ethmoid bone, the single vomer forms the nasal septum, which divides the nasal cavity into right and left sides.
Vomer
vomer
1 bone
EAR
6 bones
Malleus
2 bones
Incus
2 bones
Stapes
2 bones
is located in the neck, between the mandible and larynx. It is suspended from the styloid process of each temporal bone by ligaments and muscle.
HYOID BONE
HYOID BONE
1 bone
VERTEBRAL COLUMN
26 BONES
protects the spinal cord, supports the head and neck,
The vertebral column
FIVE SECTIONS OF THE VERTEBRAL COLUMN
Cervical vertebrae Thoracic vertebrae Lumbar vertebrae Sacrum Coccyx
Cervical vertebrae
7 BONES
Thoracic vertebrae
12 BONES
Lumbar vertebrae
5 BONES
Sacrum
1 BONE
Coccyx
1 BONE
are in the neck region.
Cervical vertebrae
Cervical vertebrae
7 BONES
are posterior to the chest
cavity and serve as
attachments for the ribs.
Thoracic vertebrae
Thoracic vertebrae
12 BONES
form the lower back.
Lumbar vertebrae
Lumbar vertebrae
5 BONES
consists of 5 fused
vertebrae and forms the posterior wall of the pelvis. Blood vessels and nerves pass through the openings.
Sacrum
Sacrum
1 BONE
sometimes referred to as the
tailbone, consists of 4 fused
vertebrae
Coccyx
NORMAL CURVATIVES OF THE SPINE
o Cervical curve
o Thoracic curve
o Lumbar curve
o Sacral curve
ABNORMAL CURVATURES
o Scoliosis
o Kyphosis
o Lordosis
is a lateral curvature of the spine, most often in the thoracic region.
Scoliosis
or “hunchback,” is an
exaggerated thoracic curvature.
Kyphosis
or “swayback,” is an exaggerated lumbar curvature.
Lordosis
projects from the laminae; it serves as attachment point for muscles.
Spinous process
are lateral extensions that serve as attachment
points for muscles.
Transverse processes
The body is the thick, disc-shaped anterior
portion that bears weight.
Body
THORACIC CAGE
25 BONES
The ribs and sternum form the framework for
the thorax.
THORACIC CAGE
attaches directly to the first through seventh pairs of ribs by a form of hyaline cartilage called costal cartilage.
Sternum
Sternum
1 bone
Ribs
24 bone
are named based on
how they attach to the sternum
ribs
rib pairs 1 through 7
true ribs
rib pairs 8 through 12
false ribs
rib pairs 11 and 12
floating ribs
The next set of bones in the upper
body is the shoulder girdles or pectoral girdles, which attach the upper limbs to the axial skeleton.
Pectoral Girdle
Attached to the scapula is the
humerus, the longest bone in the upper body.
Upper Limbs
which consists of the two hip bones.
pelvic girdle
attach to the sacrum of the vertebral column posteriorly and with each other anteriorly to form the pubic symphysis.
coxal bones or os coxa
composed of an ilium, an ischium, and a pubis that have fused to form a single unit.
coxal bone
composed of a single bone proximally with increasing numbers of bones as one moves distally.
lower limb
the longest single bone in the body.
femur (thigh bone)
formed by the coxal bones, sacrum, and coccyx.
bowl-shaped pelvis
metatarsals
5 bones
are like the metacarpals of the hand.
Metatarsals
