Chapter 8; The Skeletal System Flashcards
axial skeleton
forms the central supporting axis of the body
appendicular skeleton
includes the bones of the upper limb and pectoral girdle and the bones of the lower limb and pelvic girdle
sesamoid bones
form within some tendon in respond to strain
sutural bones
extra bones in the skull
articulated
dried bones held together by wires and rods to show their spatial relationships to each other
disarticulated
bones taken apart so their surface features
bone markings
ridges, spines, bumps, depressions, canals, pores, slits, cavities, and articular surfaces
condyle (articulation)
a rounded knob that articulates with another bone
facet (articulation)
a smooth, flat slightly concave or convex articular surface
head (articulation)
the prominent expanded end of a bone, sometimes rounded
crest (extension and projection)
a narrow ridge
epicondyle (extension and projection)
an expanded region superior to a condyle
line (extension and projection)
a slightly raised, elongated ridge
process (extension and projection)
any bony prominence
protuberance (extension and projection)
a bony outgrowth or protruding part
spine (extension and projection)
a sharp, slender, or narrow process
trochanter (extension and projection)
two massive processes unique to the femur
tubercle (extension and projection)
a small, rounded processes
tuberosity (extension and projection)
a rough elevated surface
alveolus (depression)
a pit or socket
fossa (depression)
a shallow, broad, or elongated basin
fovea (depression)
a small pit
sulcus (depression)
a groove for a tendon, nerve, or blood vessel
canal (passage and cavities)
a tubular passage or tunnel in a bone
fissure (passage and cavities)
a slit through a bone
foramen (passage and cavities)
a hole through a bone, usually round
meatus (passage and cavities)
a canal
sinus (passage and cavities)
an air-filled space in a bone
sutures
immovable joints
cranial cavity
encloses the brain
orbits
eye sockets
foramina (singular foramen)
holes that allow passage for nerves and blood vessels
cranial bones
enclose the brain
cranium
braincase
meninges
membrane
dura mater
thickest and toughest layer against the cranium
foramen magnum
where the spinal cord meets the brain
calvaria
the dome of the top of the skull (skullcap)
supraorbital foramen or notch
supraorbital nerve, artery, and vein; ophthalmic nerve
carotid canal
internal carotid artery
external acoustic meatus
sound waves to eardrum
jugular foramen
internal jugular vein; glossopharyngeal, vagus, and accessory nerves
foramen magnum
spinal cord, accessory nerve, vertebral arteries
hypoglossal canal
hypoglossal nerve to muscles of tongue
foramen ovale
mandibular division of trigeminal nerve, accessory meningeal artery
foramen rotundum
maxillary division of trigeminal nerve
optic canal
optic nerve, ophthalmic artery
superior orbital fissure
oculomotor, trochlear, and abducens nerves, ophthalmic division of trigeminal nerve, ophthalmic veins
superior orbital fissure
oculomotor, trochlear, and abducens nerves, ophthalmic division of trigeminal nerve, ophthalmic veins
inferior orbital fissure
infraorbital nerve, zygomatic nerve, infraorbital vessels
infraorbital foramen
infraorbital nerve and vessels
mental foramen
mental nerve and vessels
mandibular foramen
inferior alveolar nerves and vessels to the lower teeth
base
floor
anterior cranial fossa
crescent-shaped and accommodates the frontal lobes of the brain
middle cranial fossa
drops abruptly deeper, and accommodates the temporal lobes
posterior cranial fossa
deepest and houses a large posterior division of the brain called the cerebellum
frontal bone
extends from the forehead back to a prominent coronal suture
coronal suture
crosses the crown of the head from right to left and joins the frontal bone to the parietal bones
supraorbital margin
ridge deep to the eyebrows
supraorbital foramen
provides passage for a nerve, artery, and veins
supraorbital notch
the edge of this foramen breaks through the margin of the orbit
glabella
smooth area of the frontal bone just above the root of the nose
parietal bones
form most of the cranial roof and part of its walls
sagittal suture
between the parietal bones
coronal suture
anterior margin
lambdoid suture
the posterior margin
parietal foramen
an exit for a small vein from a blood sinus atop the brain
temporal lines
form an arc across the parietal and frontal bones
temporalis muscle
chewing muscle that converges on the mandible
temporal bone
forms the lower wall and part of the floor of the cranial cavity
squamous part
relatively flat and vertical, encircled by the squamous suture
zygomatic process
extends anteriorly to form part of the zygomatic arch
mandibular fossa
a depression where the mandible articulates with the cranium
tympanic part
small ring of bone that borders the opening of the external acoustic meatus
external acoustic meatus
ear canal
styloid process
provides attachment for muscles of the tongue, pharynx, and hyoid bone
mastoid part
lies posterior to the tympanic part
mastoid process
a prominent lump behind the earlobe and is filled with small air sinuses that communicate with the middle-ear cavity
mastoiditis
inflammation of the mastoid process
mastoid notch
a groove lies medial to the mastoid process
digastric muscle
opens the mouth
stylomastoid foramen
a passage for the facial nerve
mastoid foramen
passes a small artery and vein from the brain
petrous part
houses the middle and inner ear cavities that separates the cranial fossa from the posterior fossa
internal acoustic meatus
an opening on its posteromedial surface, allows passage of a nerve that carries signals for hearing and balance from the inner ear to the brain
carotid canal
passage for the internal carotid artery
jugular foramen
a large, irregular opening just medial to the styloid process, between the temporal and occipital bones
occipital bone
forms near the rear of the skull and much of its base
foramen magnum
admits the spinal cord to the cranial cavity
basilar part
the occipital bone continues anterior to this as a thick median plate
occipital condyle
where the skull rests on the vertebral column
hypoglossal canal
passes through it to innervate the muscles of the tongue
condylar canal
found posterior to each occipital condyle
external occipital protuberance
prominent medial bump on the occipital bone
nuchal ligament
binds the skull to the vertebral column
superior nuchal line
a ridge that can be traced horizontally from the external occipital protuberance toward the mastoid process
inferior nuchal line
provides attachment for some of the deep neck muscles
sphenoid bone
complex shape with a thick median body and outstretched greater and lesser wings which give the bone as a whole a ragged mothlike shape
optic canal
permits passage of the optic nerve and ophthalmic artery
anterior clinoid processes
a pair of bony spines of the lesser wing that appears to guard the optic foramina
superior optical fissure
a gash in the posterior wall of the orbit
sella turcica
consists of a deep pit called the hypophyseal fossa, which houses the pituitary gland
tuberculum sellae
a raised anterior margin
dorsum sellae
posterior margin
foramen rotundum and foramen ovale
passages for two branches of the trigeminal nerve
foramen spinosum
provides passage for an artery of the meninges
foramen lacerum
an irregular gash that occurs at the junction of the sphenoid, temporal, and occipital bones
posterior nasal apertures (choanae)
internal openings of the nasal cavity
medial and lateral pterygoid plates
lateral to each aperture, the sphenoid bone exhibits a pair of parallel plates
pterygoid process
narrow inferior extension between each plate
ethmoid bone
anterior cranial bone located between the eyes that contributes to the medial wall of the orbit, the roof and walls of the nasal cavity, and the nasal septum
perpendicular plate
a thin median plate of bone that forms the superior two-thirds of the nasal septum
vomer
lower part of perpendicular plate
nasal fossae
the septum divides the nasal cavity into right and left air spaces
cribriform plate
forms the roof of the nasal cavity
crista galli
an attachment point for the dura mater
cribiform (olfactory) foramina
elongated depressed area perforated with numerous holes
olfactory bulbs
rests in the cribriform foramina that are concerned with the sense of smell
labyrinth
large mass on each side of the perpendicular plate
ethmoidal cells
maze of air spaces
superior and middle nasal conchae
project into the nasal fossa from its lateral wall toward the septum
inferior nasal concha
largest of the three is a separate bone
facial bones
do not enclose the brain but lie anterior to the cranial cavity, they support the orbital, nasal, and oral cavities, shape the face, and provide attachment for the muscles of facial expression and mastication
maxillae
largest facial bones that form the upper jaw and meet each other at a median intermaxillary suture
alveolar processes
small joints of maxillary bone
alveolus
deep socket that holds the root of each tooth
infraorbital foramen
provides passage for a blood vessel to the face and a nerve that receives sensations from the nasal region and cheek
inferior orbital fissure
a gash that angles downward and medially
palate
forms the roof of the mouth and floor of the nasal cavity
hard palate
bony anterior part of mouth
soft palate
fleshy posterior part of mouth
palatine processes
horizontal extensions of the maxilla
incisive fossa
a passage for an artery to the palate and a nerve to the lower part of the nasal septum and the six front teeth
cleft palate
failure of palatine process to join normallly
palatine bones
divide the oral and nasal cavities from each other posteriorly
horizontal plate
form the posterior one-third of the bony palate
perpendicular plate
thin, delicate, irregularly shaped plate that forms part of the wall between the nasal cavity and the orbit
greater palatine foramen
nerve passage to the palate
zygomatic bones
form the angles of the cheeks at the inferolateral margins of the orbits and part of the lateral wall of each orbit
zygomaticofacial foramen
each zygomatic bone has an inverted T shape and near the intersection of the stem and crossbar of the T
lacrimal bones
form part of the medial wall of each orbit
lacrimal fossa
houses a membranous lacrimal sac in life
nasal bones
form the bridge of the nose and support cartilages that shape its lower portion
ramus
vertical to oblique posterior portion
angle
two portions meet at a corner
mental symphysis
median cartilaginous joint at the point of the chin
mental protuberance
point of the chin
mental foramen
permits the passage of nerves and blood vessels of the chin
masseter
muscle of mastication
condylar process
posterior branch of the ramus
mandibular condyle
an oval knob that articulate with the mandibular fossa of the temporal bone
temporomandibular joint
meeting of the condyle with the temporal bone forming a hinge
coronoid process
anterior branch of the ramus
mandibular notch
u-shaped arch between the two processes
mandibular foramen
on the medial surface of the ramus
auditory ossicles
consists of the malleus, incus, and stapes
hyoid bone
a slender u-shaped bone between the chin and larynx
stylohyoid ligaments and muscles
parts of the styloid process of the skull
greater and lesser horns (cornua)
hornlike projections
fontanelles
spaces between the unfused cranial bones
metopic suture
forms in kids if there frontal bones did not close
vertebral column (spine)
physically supports the skull and trunk, allows for their movement, protects the spinal cord, and absorbs stresses produced by walking, running, and lifting
vertebrae
chain of 33 in spine
cervical vertebrae
7 vertebrae in the neck
thoracic vertebrae
12 vertebrae in the chest
lumbar vertebrae
5 in the lower back
coccygeal vertebrae
4 tiny ones at the very bottom of the spine
primary curvatures
primary at birth
secondary curvature
develop later
centrum
body of a vertebrae
vertebral foramen
triangular space posterior to the body of each vertebra
vertebral canal
a passage for the spinal cord
vertebral arch
consists of the pedicle and lamina
spinous process
a projection that extends from the apex of the arch
transverse process
extends laterally from the point where the pedicle and lamina meet
superior articular processes
projects upward from one vertebra and meets a similar pair of inferior articular processes that projects downward from the vertebra above
intervertebral foramen
an opening between their pedicles
nucleus pulposus
surrounded by a ring of fibrocartilage
anulus fibrosus
a ring of fibrocartilage
herniated disc
out-pouch of nucleus
atlas
vertebra c1 (it supports the head in a manner reminiscent by Zeus to carry the heavens)
lateral mass
on each side of vertebral foramen
superior articular facet
deeply concave that articulates with the occipital condyle of the skull
inferior articular facets
comparatively flat or only slightly concave, articulate with C2
anterior and posterior arch
connects the lateral masses
anterior and posterior tubercle
slight protuberances
axis
vertebra c2 that allows rotation of the head as in gesturing “no”
dens (odontoid process)
prominent knob
transverse ligament
hold the vertebral foramen of the atlas
atlanto-occipital joint
the articulation between the atlas and the cranium
atlantoaxial joint
the one between the atlas and axis
transverse foramen
prominent round thingy that is in each transverse process
nuchal ligament
attachment provided by bifid for the back of the neck
vertebral arteries
supply the blood to the brain
vertebral veins
drain blood from various neck structures
vertebra prominens
c7
transverse costal facet
shallow cuplike feature at the end of each transverse process
costal facets
small, smooth, slightly concave spots
sacrum
bony plate that forms the posterior wall of the pelvic girdle
sacral vertebrae
lowest part of spine
anterior sacral (pelvic) foramina
allow for passage of nerves and arteries to the pelvic organs
median sacral crest
ridge that was the spinous processes of the vertebrae before fusion
lateral sacral crest
tranverse processes fuse into a less prominent feature on each side of the median crest
posterior sacral foramina
four pairs of openings for spinal nerves
sacral canal
runs through the sacrum and ends in an inferior opening called the sacral hiatus
sacral hiatus
inferior opening
auricular surface
ear-shaped region on each side of the sacrum
sacroiliac joint
strong, nearly immovable feature that is on the hip bone
sacral promontory
supports the body of vertebra L5
superior articular processes
articulates with the vertebra L5
alae
large, rough, winglike extensions
coccygeal vertebrae
four tiny features that fuse by age 20-30 that form the coccyx
coccyx
made from 4 vertebrae that are fused
horns (cornua)
serve as an attachment points for ligaments that bind the coccyx to the sacrum
thoracic cage
consists of the thoracic vertebrae, sternum, and ribs
costal margin
arc of lower ribs
sternum
bony plate anterior to the heart
manubrium
broad superior portion, shaped like the knot of a necktie
suprasternal (jugular) notch
between the two clavicles
clavicular notches
articulates with the clavicles
gladiolus
longest part of the sternum
sternal angle
can be palpated as a transverse
siphoid process
provides attachment for some of the abdominal muscles
ribs
12 pairs
costal cartilage
anterior attachment is by way of a long strip of hyaline cartilage
tubercle
point of attachment to the transverse costal facet of the same vertebra
superior articular facet
joins the inferior costal facet of the vertebra above
inferior articular facet
joins the superior costal facet of vertebra below
costal groove
marks the path of the intercostal blood vessels and nerve
true ribs
ribs 1-7
false ribs
ribs 8-12
floating ribs
ribs 11 and 12
pectoral girdle
supports the arm and links it to the axial skeleton
clavicle
collarbone
scapula
shoulder blade
sternoclavicular joint
medial end of the clavicle articulation with the sternum
acromioclavicular joint
lateral end articulates with the scapula
glenohumeral joint
scapula articulates with the humerus
sternal end
rounded, hammerlike head
acromial end
markedly flattened
conoid tubercle
a ligament attachment that faces toward the rear and slightly downward
acromion
platelike extension of the scapular spine that forms the apex of the shoulder
coracoid process
vague resemblance to a crew’s beak
glenoid cavity
shallow socket that articulates with the head of the humerus, forming the glenohumeral joint
humerus
head that articulates with the glenoid cavity of the scapula
anatomical neck
smooth surface of the head is bordered by a groove
intertubercular sulcus
between the greater and lesser tubercles that accomodates a tendon of the biceps muscle
surgical neck
narrowing of the bone just distal to the tubercles
deltoid tuberosity
an insertion for the deltoid muscle of the shoulder
capitulum
lateral side of the humerus that is shaped like a wide tire and articulates with the radius
trochlea
pulleylike and articulates with the ulna