LAB4 Flashcards
what does the skeletal system do?
- supports the weight of the body
- works together with the muscles to maintain body position and produce controlled movements
- involved in mineral
and lipid storage (mineral homeostasis) - site of blood cell production (hemopoiesis)
- protects organs from physical damage
how do bones respond to stresses placed on them?
growing thicker and stronger with exercise or becoming thin and brittle with inactivity
what bone tissues are adult bone made up of?
compact bone tissue and spongy bone tissue
what is the central canal?
Central region of osteon containing blood vessels and nerves
- blood vessels, nerves, and lymphatic tissue allows bone to receive nutrients, remove wastes, and be controlled by the nervous system
what are bone lacunae?
Spaces between lamellae that house osteocytes
what are osteocytes?
Mature bone cells that maintain bone (i.e., maintains metabolic processes such as nutrient/waste exhange with blood)
what are concentric bone lamellae?
Ring-shaped layers of collagen and calcified extracellular matrix
what are bone canaliculi?
Small canals between lacunae that connect osteocytes; provides osteocytes with nutrients and a pathway for communication
what are bone trabeculae?
Functional unit of spongy bone; arranged in an irregular lattice to make space for red bone marrow
what are osteoblasts?
immature osteocytes, build bone (bone deposition); secretes extracellular matrix and initiates calcification
what do osteoclasts do?
remodel bone through bone resorption
what is the function of the osteocyte’s cytoplasmic extensions?
Allows osteocytes to communicate with each other for processes such as movement
- Runs throughout canaliculi of bone to other osteocytes (connected by gap junctions)
where is spongy bone tissue found?
Hip bones, ribs, sternum, skull
Where do the osteocytes of spongy bone obtain their nutrients and oxygen, since there is no
central (Haversian) canal?
Red and yellow bone marrow have many blood vessels that give osteocytes in spongy bone nutrients and oxygen.
what is the function of red bone marrow?
- produces red blood cells, white blood cells, and platelets via hemopoiesis
- Mainly composed of developing blood cells, adipocytes, macrophages, and fibroblasts
what is the function of yellow bone marrow?
- Stores triglycerides, which are a potential chemical energy reserve - Mainly made from adipocytes
which adult bones contain red bone marrow?
hip bones, ribs, sternum, vertebrae, skull, ends of humerus and femur
what are the epipheses?
Proximal and distant ends of bone; primarily functions to form joints with other bones or attachments to muscles.
what is the diaphysis/shaft?
Long, cylindrical, main portion of bone. Provides the bone with strong support without too much weight.
what is the periosteum?
- layer of connective tissue surrounding bone
- Outer fibrous layer of dense connective tissue protects bone
- inner osteogenic layer is composed of osteopregenitor cells (area of bone production)
- Nourishes the bone through periosteal arteries (provides nutrients)
what is the endosteum?
Thin membrane lining medullary cavity and internal spaces of spongy bone
- Contains single layer of osteoregenitor cells and some connective tissue
what are osteoprogenitor cells?
bone stem cells, usually found in areas of bone production
what is the medullary cavity?
Hollow, cylindrical region within diaphysis
- Contains yellow bone marrow and blood vessels (blood vessels give nutrients to the bone)
- Allows bone to be strong while minimizing weight
what is the epiphyseal plate/line?
Area in each epihphyses consisting of hyaline cartilage, which allows the diaphysis to grow in length via endochondral ossification
what does the appendicular division of the skeleton include?
the pectoral girdle, pelvic
girdle, upper and lower limbs
what does the axial division of the skeleton include?
the skull, vertebrae,
sternum, ribs and hyoid bone
what is the function of the axial skeleton?
- provides a framework for the attachment
of the structures of the appendicular skeleton - protecting internal organs such as the heart, lungs and brain
what is the foramen/foramina?
Hole/opening; allows passageway of blood vessels, nerves, or ligaments.
what is the fossa?
Shallow depression; acts as attachment point (for other bones/muscles) for articulation
what is the meatus?
Tubelike opening; passageway for blood vessels, nerves, or ligaments
what is the process?
Projection/outgrowth; forms joints or acts as attachment points for ligaments and tendons
what is the condyle?
Large, round protuberance. Has smooth articular surface at end of bone.
what is the crest?
Prominent ridge; forms attachment points
what is the facet?
Smooth, flat, slightly concave or convex surface. Forms joints
what is the head?
Process; rounded articular projection supported on neck of bone; forms joints
what is the frontal cranial bone?
Forms the forehead, roofs of orbits, and anterior part of cranial base
what is the ethmoid bone?
Located anterior to sphenoid and posterior to nasal bones.
Forms:
- part of anterior portion of cranial base
- medial wall of orbits
- superior part of nasal septum
- most of superior side walls of nasal cavity
what is the occipital bone?
Forms posterior region of cranial cavity and most of cranium base. Foramen magnum allows medulla oblongata and spinal cord to connect. Occipital condyles articulate with C1, forming atlanto-occipital joint.
what is the sphenoid bone?
Lies in middle of cranial base. Articulates with all other cranial bones, holding them together.
what is the parietal bones?
Forms greater portion of sides and roof of cranial cavity. Contains many blood vessels that supply the sura mater.
what is the temporal bone?
Forms inferior lateral parts of cranial cavity, part of cranial base. Forms zygomatic arch with zygomatic bones (via zygomatic process).
- Mandibular fossa (on zygomatic bone) and articular tubercle articulates with mandible
- Mastoid process; rounded projection on mastoid region, serves as attachment point for multiple neck muscles.
- Styloid process; attachment point for muscles and ligaments of tongue and neck
- external auditory meatus; directs sound waves into the ear
what is the mandible?
Largest, strongest facial bone. Only moveable bone in skull. Articulates with temporal bone to form temporomandibular joint.
what is the maxilla?
Articulates with every bone except mandible; mainly forms most of hard palate.
Infraorbital foramen; allows passageway of infraorbital blood vessels
Palatine process; horizontal projection of maxilla forming part of hard palate.
what is the zygomatic bone?
Forms prominences of cheeks, lateral wall and floor of orbits
what is the palatine bone?
L-shaped bones; forms posterior part of hard palate, small part of orbit
what is the vomer bone?
Triangular bone; forms inferior part of nasal septum.
what is the inferior nasal concha?
Forms part of inferior lateral wall of nasal cavity. Increases surface are of nasal cavity and allows air to be filtered before being sent to lungs.
what is the nasal bone?
Forms nose bridge; attachment point for some thin facial expression muscles
what is the lacrimal bone?
Small, fragile bones; contains lacrimal fossa that has lacrimal sac, which collects tears and passes them to nasal cavity.
List the bones that make up the bony wall of the orbits
Maxillae, frontal bone, zygomatic bones, ehtmoid, lacrimal bones, sphenoid, palatine bones
list the unpaired cranial and facial bones
Cranial: ethmoid, sphenoid, occipital bone, frontal bone
Facial: vomer, mandible
what are the bones that make up the hard palate?
Maxillae, palatine bones
what are the bones that form the nasal septum?
Vomer, ethmoid (perpendicular plate), septal nasal cartilage
what bones form the zygomatic arch?
Zygomatic bone (temporal process), temporal bone (zygomatic process)
what is the primary function of the cranial bones?
Protection of the brain from physical damage
what are the primary functions of the facial bones?
Creates framework of the face, provides support for entrances to digestive and respiratory systems.
what are three bones in the skull involved in articulations?
- mandible
- temporal bone
-sphenoid bone
what is the coronal suture?
Connects the frontal bone to the parietal bones
what is the sagittal suture?
Connects the parietal bones
what is the lambdoid suture?
Connects to parietal bones to the occipital bone
what is the squamous suture?
Connects the parietal and temporal bones
what are sutures?
immoveable joints found only in the skull
- holds bone of the skull together
what are fontanels?
soft spots on a newborn skull
- areas where ossification was not yet complete
what is the function of fontanels?
- allows bones to compress during birth
- permit rapid growth of the brain
what is the anterior fontanel?
Roughly diamond shaped, located on midline of perietal bones and frontal bone
what is the posterior fontanel?
Located at midline of parietal bones and occipital bone
what is the anterolateral fontanel?
Located laterally among frontal, parietal, and sphenoid bones. Small and irregularly shaped.
what is the posterolateral fontanel?
Located laterally among occipital, parietal, and temporal bones. Irregularly shaped.
what are the functions of the paranasal sinuses?
- Allows skull to increase in size without changing the mass of bones
- Acts as a resonating chamber for the voice, enhancing it
- Increases surface area for the nasal mucosa, increasing mucus production, which helps to moisten and purify air
what important muscle is attached to the hyoid bone?
the tongue
what is the malleus ossicle?
hammer
- Small bone in middle ear
- Sends vibrations from eardrum to incus
what is the incus ossicle?
- anvil-shaped
- small bone in middle ear
- sends vibrations from malleus to stapes
what is the stapes ossicle?
- stirrup-shaped
- small bone in middle ear
- sends vibration from incus to inner ear
what is the vertebral column?
- supports the head
- protects the spinal cord
- provides attachment
points for back and abdominal muscles
what are intervertebral discs?
- found between the
vertebrae from the cervical region to the sacrum - made of fibrocartilage that
cushion and absorb vertical shocks
what is the body/centrum of the vertebra?
Thick, disc-shaped portion of vertebra; weight-bearing
what is the vertebral foramen?
Opening through which the spinal cord can pass through
what is the transverse process?
Process extending laterally where lamina and pedicle join. Attachment point for muscles.
what is the spinous process?
Process extending posteriorly between junction of laminae. Attachment point for muscles.
what is the superior articular process?
Process extending/facing upward on each side of vertebrae. Articulates (makes joint) with inferior articular processes of vertebra above.
what is the inferior articular process?
Process extending/facing downward on each side of vertebrae. Articulates with superior articular processes of vertebra below.
what are the facets on the superior and inferior articular processes?
Smooth, flat surface covered by hyaline cartilage on aticular processes; allows articulation of vertebrae to one another (intervertebral joints)
what are the five regions of the vertebral column?
- cervical (C1 - C7)
- thoracic (T1 - T12)
- lumbar (L1 - L5)
- sacrum (5 sacral bones)
- coccyx (3-4 coccygeal)
what are some characteristics of the atlas?
- highly specialized to perform specific functions
- large superior articular facets that articulate with occipital condyles of the skull
- lacks a body and spinous process
what are the characteristics of the axis?
- highly specialized to perform specific functions
- can be identified by peg-like process projecting superiorly from the body, called the dens or odontoid process
what is the odontoid process/dens?
peg-like process projecting superiorly from the body
what two features make cervical vertebrae easily identifiable?
- The tips of the spinous processes of C2-C6 are bifid
- The transverse processes have a transverse foramen
which pair of bones articulate to allow you to nod?
atlas and occipital bone
- connected by atlanto-occipital joint
which bones allow you to rotate your head from side to side?
axis and atlas
how can you identify thoracic vertebrae?
- easily identified by the facets for rib articulations
- body has two small articulating surfaces on each side, a superior and inferior costal facet (demifacet), which articulate with the head of the ribs
- each transverse process has an articular facet for the tubercle of the rib
how do you identify the five lumbar vertebrae?
- largest
- have short, thick processes for the attachment of large back muscles
how do you identify the sacrum?
- formed of five fused vertebrae
- articulates with the pelvic girdle at the sacroiliac joints
what is the vertebral canal formed by?
the vertebral foramen
where does the vertebral canal terminate?
- vertebral canal continues through sacrum as the sacral canal
- terminates at the sacral hiatus, just above coccyx
what is the coccyx formed by?
- formed by the union of 3/5 bones
what is the thoracic cage formed by?
- sternum
- ribs
- costal cartilages
what three parts is the sternum composed of?
- manubrium
- body
- xiphoid process
when does the xiphoid process typically fuse?
fuses to the body by age 25
how many pairs of rips articulate with the thoracic vertebrae posteriorly?
twelve pairs of ribs
what are the true ribs?
the first seven pairs of ribs
- attaches to sternum anteriorly and directly by their own costal cartilage
what are the false ribs?
- last 5 pairs of ribs
- costal cartilages do not attach directly to sterum
- cartilages of 8 9 and 10 ribs attach to each other and then to cartilage of 7th rib
- last two pairs have no sternal attachment
what are floating ribs?
- last two pairs of ribs
- have no sternal attachment
what type of tissue forms the costal cartilages?
- hyaline cartilage
name 4 bones whose primary function is to protect brain from trauma
- frontal
- parietal
- temporal
- occipital
name 3 bones that contain a paranasal sinus
- maxillae
- sphenoid
- ethmoid
- frontal
describe how to differentiate between the three different types of ribs
- True (vertebrosternal) ribs - connects to sternum directly
- False (vertebrochondral) ribs - connects to costal cartilages of each other, then to cartilages of 7th pair of ribs
- Floating ribs - Does not connect to the sternum at all
name 3 bones of the skull that have a foramen
- occipital
- mandible
- frontal
name 3 features/marking common to all vertebrae
- vertebral body/ centrum
- vertebral arch
- spinous process
what is the hyoid bone?
- bone suspended from styloid process of the temporal bone by muscles and ligaments
- does not articulate with any other bones
