CH 7 & CH 8 Skull Flashcards
Osteology
the study of bone
Functions of Skeletal System
Acid-base balance, Blood formation, Protection (viscera), support
Calcification
deposition of calcium salts
What shape bone are vertebrae?
Irregular Shape
Ossification
process in which dense regular connective tissue hardens to form bone
Compact Bone
Bone tissue made up of parallel osteons that are tightly packed together
Diaphysis of long bone is made of what bone type?
Compact bone
Spongy (trabecular) Bone
always enclosed by more durable compact bone. Found in epiphysis of bones, distinguished by trabeculae
Eiphysis
expanded end of a long bone to which tendons and ligaments attach
Diaphysis
shaft of a long bone
Nutrient Foramen
Allows the passage of blood vessels into the bone
Perforating Fibers
Collagen fibers from the periosteum that firmly adhere the periosteum to the bone
Osteoblasts
cells that build new bone and are located in the osteogenic layer of the periosteum
Diploe
spongy bone tissue sandwiched between 2 layers of compact bone in the skull
Periosteum
connective tissue surrounding external surface of a bone
Osteogenic Cells
stem cells in the endosteum, periosteum, and central canals that become osteoblasts
What hormone do osteoblasts secrete?
Calcitonin
Endosteum
layer of connective tissue lining internal surfaces of bones
Canaliculi
narrow channels connecting neighboring lacunae in osseous tissue
Functions of Osteocytes
act as strain sensors to adjust bone shape and density to adapt to stress, also resorb bone, and deposit bone
Function of osteoclasts
Osteolysis (kill osteocytes)
Substance that makes up part of matrix of the bone
Calcium phosphate salt (part of the inorganic matter)
By dry weight, most of the matrix of bone is made of…
inorganic matter
Function of osteoblasts
produce the organic component of bone matrix
Lamellae
concentric rings of compact bone (the layers of bony matrix)
Where are lacunae located?
between the lamellae
Osteoclasts
bone dissolving cells on bone surfaces
What makes up the inorganic part of bone matrix?
Hydroxyapatite
Haversian or Central Canal
channel that extends longitudinally through the center of an osteon
Organic matter of bone matrix
constitutes 1/3 of dry weight, synthesized by osteoblasts and contains collagen and various protein-carbohydrate complexes
Inorganic matter of bone matrix
2/3 of dry weight, made up of about 85% hydroxyapatite (crystalized calcium phosphate salt)
Interstitial Lamellae
the irregular regions between osteons that contain the remains of old osteons
Red Bone Marrow
fills space between trabeculae in the epiphysis of a long bone (aka Myeloid Tissue) contains hemapoietic stem cells that generate red blood cells
Yellow Bone Marrow
Found in medullary (marrow) cavity of the diaphysis
Where is red bone marrow found in children?
In almost every bone. As an adult, it changes to yellow bone marrow
What is yellow bone marrow made of?
adipose cells that store energy (fat)
Where is red bone marrow found in adults?
axial skeleton, pectoral and pelvic girdle
Parathyroid Hormone (PTH) Release
stimulated by low blood calcium level , raises blood calcium level
Calcitriol
raises blood phosphate levels
How are most fractures repaired?
By closed reduction (reset and held in place with a cast)
Stress Fracture
fracture in a healthy bone caused by abnormal trauma like a fall
Open Reduction
when surgery is needed to reset a fracture
Osteogenesis imperfecta
defect in collagen deposition that causes bones to be exceptionally brittle
Osteomalacia
softening of the bone due to decrease in mineralization
Osteomyelitis
an infection of the bone
Orthopedics
branch of medicine dealing with bone disorders
Osteitis Deformans
Excessive osteoclast proliferation resulting in weak, deformed bones (Paget Disease)
Sesamoid bone
forms within a tendon due to stress (ex Patella)
Head
prominent expanded end of a bone that is sometimes round
Spine
a sharp, slender, or narrow process of a bone
Alveolus
a pit or socket (tooth socket)
Fossa
a shallow, broad, or elongated basin
Fovea
a small pit
Sulcus
a groove for a tendon, nerve, or blood vessel in cranium
Condyle
a rounded knob that articulates with another bone
Facet
a smooth, flat, articular surface
Crest
a narrow ridge
Epicondyle
an extended region superior to a condyle
Line
slightly raised, elongated ridge
Protuberance
a bony outgrowth or protruding part
Tubercle
a small, rounded process
The Sinuses
Spheniod, ethmoid, frontal, and maxillary
Paranasal Sinuses
add resonance to the voice and lighten the anterior portion of the skull
Calvaria
the group of bones that form the roof and walls of the skull
Anterior cranial fossa
houses frontal lobe
Middle cranial fossa
houses temporal lobes
Posterior cranial fossa
Houses cerebellum
Bones of the Cranium
Frontal, parietal, occipital, temporal, ethmoid, and sphenoid bones
Glabella
smooth, flat bone between supraorbital bones
Tympanic part of temporal bone
features the external acoustic meatus and the styloid process
Squamous part of temporal bone
flat and vertical part that contains the zygomatic process and mandibular fossa
Mastoid Part of temporal bone
posterior to tympanic part, filled with small air sinuses that communicate with middle ear cavity. Features mastoid process and mastoid foramen
Petrous part of temporal bone
contains the internal acoustic meatus and the middle and inner ear cavities and carotid canal and jugular foramen
Styloid Process
provides a site of attachment on the temporal bone for muscles of the tongue, pharynx, and hyoid bone
Stylomastoid foramen
passage in temporal bone for facial nerve
Occipital condyles
where the skull rests on the vertebral column
Mastoid Process
prominent bump behind and below the ear that is filled with small air sinuses and serves as an attachment for major neck muscles
Inferior Nuchal Line
attachment site for some deep neck muscles
Lesser wing of Sphenoid bone
forms posterior margin of the anterior cranial fossa
Greater wing of the sphenoid bone
forms one half of the middle cranial fossa and part of the lateral surface of the cranium
Sella turcia
saddle-like prominence in the body of the sphenoid bone that houses pituitary gland
Cribiform plate
thin medial plate of bone that forms the superior part of the nasal septum
Crista Galli
attachment site for dura mater
Superior nasal conchae
has sensory cells of smell
within the nasal septum, the perpendicular plate is part of…
the ethmoid bone
Palatine Process
processes of maxillary bone that forms the anterior 2/3 of the hard palate
Lacrimal bone
located between the maxillary and ethmoid bone and forms part of medial wall of orbit
Mental protuberance
chin
Nasal Septum
formed by Vomer and ethmoid bones
Auditory Ossicles
malleus, incus, and stapes. One set of 3 in each middle ear cavity. Part of the 7 bones closely associated with the skull but not apart of it. 7th bone is Hyoid bone (only bone in body that doesn’t articulate with another bone. It is suspended above larynx but cartilage attached at sphenoid bone)
What does the mandiublar condyle articulate with?
the mandibular fossa
4 prominent fontanelles
anterior, posterior, sphenoid, and mastoid
Trochanter
to massive processes unique to the femur
Tuberosity
a rough, elevated surface
Process
any bony prominence
Canal
a tubular passage or tunnel in a bone
Fissure
a slit through a bone
Foramen
a hole through a bone, usually round
Meatus
a canal (associated with the ear)
Sinus
an air filled space in a bone
