Bio Midterm #2 Flashcards
Bone
hard, dense connective tissue
Supports the structure of the body
Cartilage
Semi-rigid form of connective tissue
provides flexibility and smooth surfaces for movement
Bone matrix
acts as a reservoir for minerals important to the functioning of the body - calcium and phosphorus
Yellow marrow
contains adipose tissue
triglycerides stores in the adipocytes of the tissue can serve as a source of energy
Red marrow
where hematopoiesis takes place
red blood cells, white blood cells, and platelets are all produced here
Hematopoiesis
the production of blood cells
Long bone
cylindrical in shape
longer than it is wide
humerus, ulna, radius, femur, tibia, fibula, metacarpals, metatarsals, phalanges
they move when muscles contract
Short bone
equal in length and width, cube shaped
are only found in the carpals of the wrists and metatarsals of the ankles
provide stability and support
Flat bones
typically thin and often curved
cranial bones, scapulae, sternum, and ribs
serve as points of attachment for muscles
often protect internal organs
Irregular bones
does not fit into any other classification
vertebrae, many facial bones
Sesamoid bones
small round bone
form in tendons and protect them by overcoming compressive forces
Typically found in tendons associated with feet, hands, knees
patella
Diaphysis
tubular shaft that runs between the proximal and distal ends of the bone
its walls are composed of dense and hard compact bone
Medullary cavity
hollow region in the diaphysis which is filled with yellow marrow
Epiphysis
wider end of the bone
filled with spongy bone
red marrow fills the spaces in spongy bone
Metaphysis
where the epiphysis meets the diaphysis
is the narrow area that contain the epiphyseal plate or growth plate
Epiphyseal plate
a layer if hyaline cartilage in a growing bone
when the bone stops growing it is replaced by osseous tissue and the plate become an epiphyseal line
Endosteum
the membrane lining inside the medullary cavity
bone growth, repair, and remodelling occur here
Periosteum
the membrane that lines the outside of the bone
contains blood vessels, nerves, and lymphatic vessels that will nourish compact bone
covers everywhere expect for where the epiphyses meet other bones to form joints
Articular cartilage
covers the area of the epiphyses that meet other bones to form joints
is a thin layer of cartilage that reduces friction and acts as a shock absorber
Dipolë
a layer of spongy bone found in flat bones
lined on either side by a layer of compact bone
Articulation
where two bone surfaces come together
surfaces tend to conform to one another - one being rounded and the other being cupped
Projection
area of a bone that projects above the surface of the bone
serves as attachment points for tendons and ligaments
size and shape are indicators of the forces exerted through the attachment of the bone
Hole
an opening or groove in the bone that allows blood vessels and nerves to enter the bone
Head
prominent rounded surface
articulation
Facet
flat surface
articulation
Condyle
Rounded surface
articulation
Protuberance
protruding
projection
Process
prominence feature
projection
Spine
sharp process
projection
Tubercle
small rounded process
progection
Tuberosity
rough surface
projection
Line
slight, elongated ridge
projection
Crest
ridge
projection
Fossa
elongated basin
Fovea
small pit
Sulcus
groove
Canal
passage in bone
Fissure
slit through bone
Foramen
hole through bone
Meatus
opening into canal
Sinus
air-filled space in bone
Collagen fibres in bone matrix
provides a surface for inorganic salt crystals to adhere to
give bones flexibility so that they are not brittle
Salt crystals
forms when calcium phosphate and calcium carbonate combine to create hydroxyapatite
calcifies on the collagen fibres
Hydroxyapatite crystals
gives bones their hardness and strength
Osteoblast
bone cell responsible for forming new bone
found in growing portions of the bone - periosteum and endosteum
do not divide
synthesize and secrete the collagen matrix and calcium salts
changes structure and becomes and osteocyte
Osteocyte
primary cell of mature bone
located in a space called a lacuna and is surrounded by bone tissue
maintain the mineral concentration of the matrix
communicate with other osteocytes via canaliculi channels within the bone matirx
Osteogenic cell
undifferentiated with high mitotic activity
only bone cells that divide
found deep in the periosteum and marrow
these cells differentiate and develop into osteoblasts
Osteoclast
responsible for bone reabsorption, or breakdown
found on bone surfaces
originate from white blood cells - monocytes and macrophages
Compact bone
stronger than spongy bone
found under the periosteum and in the diaphyses of long bones
composed of osteons
Osteons
structural unit of compact bone
composed of concentric rings of calcified matrix called lamellae
Central canal
the centre of the osteon where blood vessels, nerves and lymphatic vessels are contained
Perforating canal
extend to the periosteum and endosteum
vessels and nerves from the central canal branch off into the perforating canal
Spongy bone
aka cancellous bone
contains osteocytes housed in lacunae but they are not arranged in concentric circles
Lamellae
the concentric rings of calcified matrix in the osteons
Lacunae
spaces found at the borders of adjacent lamellae
where osteocytes are housed
Trabeculae
structural unit of spongy bone
lacunae and osteocytes are in a lattice network of matrix spikes - spongy bone
Nutrient foramen (foramina - plural)
where spongy bone and the medullary cavity receive nourishment from arteries
a small opening in the diaphysis
Ossification (osteogenesis)
process of bone development
Cartilage templates
bone uses a model tissue to lay down its mineral matrix
the cartilage template is the most common for skeletal development
the framework is a flexible, semi-solid matrix of chondroblasts and others substances
throughout fetal development bone forms on the cartilaginous matrix
chondrocytes
chondroblasts that are isolated by matrix
Intramembranous ossification
compact and spongy bone develops directly from sheets of mesenchymal (undifferentiated) connective tissue
mesenchymal cells gather and differentiate - some will become osteogenic cells and then osteoblasts
flat bones of the face, most cranial bones, and clavicles are formed this way
begins in utero and continues into adolescence
Ossification center
what early osteoblasts that appear in a cluster are called
Osteoid
uncalcified matrix that is secreted by osteoblasts
will harden and trap the osteoblasts, where they will become osteocytes
Endochondral Ossification
bone develops by replacing hyaline cartilage
takes much longer than intramembranous ossification
bones at the base of the skull and long bones form this way
some mesenchymal cells differentiate into chondrocytes that from the cartilage template
Perichondrium
a membrane that covers the cartilage in endochondral ossification
Reserve zone
region closest to the epiphyseal end of the plate and contains small chondrocytes within the matrix
Proliferative zone
next layer towards the diaphysis, contains stacks of slightly larger chondrocytes
makes new chondrocytes
Zone of maturation and hypertrophy
even larger chondrocytes, closer to the diaphysial end of the plate
longitudinal growth of the bones is a result of the cellular division in this zone and the proliferative zone
Zone of calcified matrix
connects the epiphyseal plate to the diaphysis
chondorcytes are dead and the matrix is calcifies - osteoblasts secrete bone tissue
bone grows in length when osseous tissues is added to the diaphysis
Appositional growth
when bones grow in diameter
the medullary cavity diameter increases due to the osteoclasts
the diameter of the bone increases due to osteoblasts
this process is called modelling
Remodelling
reabsorption of old or damaged bone takes place on the same surface where osteoblasts lay new bone
Fracture
broken bone
Closed reduction
when a broken bone is manipulated into is natural position without surgery
Open reduction
requires surgery to reset the bone
Transverse fracture
occurs straight across the long axis of the bone
Oblique fracture
occurs at an angle that is not 90 degrees
Spiral fracture
bone segments are pulled apart as a result of a twisting motion
Comminuted fracture
several breaks result in many small pieces between two large segments
Impacted fracture
one fragment is driven into the other
Greenstick fracture
a partial fracture
Open or compound fracture
bone has broken through the skin
closed fracture
bone has not broken through the skin
Fracture hematoma
blood from the bone has formed a clot
the disruption of blood flow to the bone results in the death of bone cells around the fracture
Internal callus
formed by the chondrocytes from the endosteum
secretions of fibrocartilaginous matrix from the chondrocytes between the two ends of bone
External callus
formed by the periosteal chondrocytes and osteoblasts around the outside of the break
stabilized the fracture
hyaline cartilage and bone
Calcium
needed to from hydroxyapatite crystals that give bone its hardness
Vitamin D
needed for calcium absorption
Vitamin K
supports bone mineralization
Magnesium and flouride
structural component of bone
omega-3 fatty acids
reduces inflammation that may interfere with osteoblast function
NRSGHypocalcemia
abnormally low levels of calcium
results in problems with blood coagulation, muscle contraction, nerve functioning, and bone strength
Calcium homeostasis
maintaining a blood calcium level of about 10 mg/dL
Hypercalcemia
abnormally high levels of calcium
lethargy, sluggish reflexes, constipation, loss of appetite, confusion, coma
Axial Skeleton
includes all bones of the head, neck, chest, and back
protects the brain spinal cord, heart, and lungs
consists of 80 bones
Skull
formed by 22 bones
Vertebral column
consists of 24 bone, called vertebra (mobile)
7 cervical
12 thoracic
5 lumbar
plus the sacrum and coccyx (fused)
Thoracic cage
12 pairs of ribs and the sternum
Appendicular skeleton
includes all bones of the upper and lower limbs
126 bones
Cranium
skull
is subdivided into the facial bones and the brain case (cranial vault)
Mandible
lower jaw
the only moveable bone of the skull
Brain case
surrounds and protects the brain and houses the middle and inner ear structures
formed by 8 bones
Orbit
bony socket that houses the eyeball and the muscles that move the eye
supraorbital margin
upper margin of the anterior orbit
supraorbital foramen
near the middle of the supraorbital margin is a small opening
provides passage of a sensory nerve to the skin of the forehead
Infraorbital foramen
below the orbit
point of emergence for a sensory nerve that supplies the anterior face below the orbit
Nasal septum
divides the nasal cavity into halves
Perpendicular plate of the ethmoid bone
upper portion of the nasal septum
Vomer bone
lower portion of the nasal septum
Inferior nasal concha
a bony plate projecting from each lateral wall of the nasal cavity
middle nasal concha
located just above the inferior nasal concha
part of the ethmoid bone
superior nasal concha
much smaller than the other two
located laterally to the perpendicular plate in the upper nasal cavity
Zygomatic arch
bony arch on the side of the skull that spans from the area of cheek to just above the ear canal
formed by the junction of two bony processes
temporal process of the zygomatic bone
the cheekbone
zygomatic process of the temporal bone
longer posterior portion of the zygomatic arch
temporal fossa
above the zygomatic arch is a shallow space
infratemporal fossa
below the zygomatic arch
calvaria
skullcap
rounded top of the skull
cranial fossa’s
anterior cranial fossa
middle cranial fossa
posterior cranial fossa
from anterior to posterior the fossae increase in depth
