Skeletal System Flashcards
What are the functions of the Skeletal System
support, protection, production of erythrocytes and immune cells, storage of minerals, movement
what is the axial skeleton?
Skull, vertebral column, sternum, ribs
what is the appendicular skeleton?
pectoral girdle, pelvic girdle, limbs
How does dermal bone develop?
within dermis, formed vis intramembranous ossification
how does endochondral bone develop?
within hyaline cartilage precursor model, formed via endochondral ossification
Where did the first bone originate and evolve from?
dermal armor of ostracoderms
List the process of intramembranous ossification
osteoprogenitor cells accumulate within the dermis, become osteoblasts, and produce osteoid which is enriched with calcium and salts to form trabeculae, osteoblasts “trapped” in the new bone become osteocytes
List the process of endochondral ossification
bone collar forms around hyaline cartilage model, hyaline cartilage within the bone model forms cavity, internal cavities invaded by the periosteal bud and spongy bone formation, medullary cavity forms as ossification continues, ossification epiphysis when completed, hyaline cartilage only remains in the epiphyseal plates and articular cartilages
what is the periosteum?
vascularized connective tissue covering of bones which connects to tendons and ligaments and anchors blood vessels and nerves
what increases the girth of long bones?
bone deposition under the periosteum
T/F: In mammals, epiphyseal plates ossify
False, remain cartilaginous to allow for bone lengthening until adult.
What is determinate growth?
Epiphyseal plates remain cartilaginous to allow for bone lengthening until adult
What is indeterminate growth?
Bones continue to grow throughout life
What is the synovial cavity?
space between bones filled with synovial fluid for cushioning
What are the two types of joint?
Diathrosis, and Synarthrosis
What are diarthrosis joints?
most common, moveable type of joint, between bones
what are synarthrosis joints?
joints with limited movement but room for growth, sutures where 2 dermal bones articulate (skull, shell of turtles)
What is the articular capsule?
fibrous connective tissue capsule surrounding joints, unites articulating bones
What is articular cartilage?
ends of bones of joint-covered hyaline cartilage absorb shock and reduce friction during movement
what is the bursa?
fluid-filled sac filled with synovial fluid produced by synovial membrane, provides cushion reduces friction
What is chondrocranium?
endochondral bone mostly derived from mesoderm
supports brain and sense organs, envelops brain in chondrichthyans
What is Splanchocranium
endochondral bone derived from the neural crest forms pharyngeal arches derivates
what is chondrocranium in vertebrates other than chodnricthyans?
endochondral bone
where does cartilage form during development?
under brain and next to notochord
Trabeculae form and develop into the __________
ethmoid plate (nerual crest origin)
parachordal(cartilaginous rods) from and develop into the __________
Basal plate (part of the sphenoid bone)
what do the sensory capsules include?
nasal, optic, and otic
T/F: in chondrichthyans, the chondrocranium envelops the entire brain and ossifies
False, does not ossify
T/F: The chondrocranium is reduced to the floor of the skull in most vertebrates, supporting the brain
true
What is the splanchnocranium in vertebrates other than chondrichthyans?
endochondral bone
in gnathostomes, the splanchnocranium is made up of _____ and functions in _________
pharyngeal arches that support gills and contribute to jaw formation
In gnathostomes, the 7 pharyngeal arches are modified to form
mandibular arch (1st), hyoid arch (2nd), branchial arches (3rd-7th)
what is the spiracle?
modified pharyngeal slit between the mandibular and hyoid arches
what are the 4 pairs of cartilage elements that each branchial arch consists of and what are they united by?
pharyngobranchial, epibranchial, ceratobranchial, hypobranchial, united by single basibranchial cartilage
What are the homologies of the hyomandibular cartilage?
hyomandibula in bony fishes
columella/stapes in amphibians, reptiles, birds, and mammals
What are the homologies of the quadrate process of the palatoquadrate?
quadrate in bony fishes, amphibians, reptiles, and birds
incus in mammals
What are the homologies of the meckels cartilage?
articular in bony fishes, amphibians, reptiles, and birds
malleus in mammals
What are the homologies of portions of ceratohyal, basihyal, and branchial arches I and II?
pharyngeal arches III and IV in sharks and bony fishes
hyoid in amphibians, reptiles, birds, and mammals
What are the homologies of portions of ceratohyal, basihyal, and branchial arches II and III?
pharyngeal arches IV and V in bony fishes and sharks
cartilaginous elements of larynx in amphibians, reptiles, birds, and mammals
What are the homologies of portions of branchial arches IV and V?
pharyngeal arches Vi, VIII in sharks and bony fishes
not present in amphibians, reptiles, mammals, and birds
What are the homologies of the palatoquadrate palatal region?
epipterygoid in bony fishes, reptiles, birds, and amphibians
alisphenoid (greater wing of sphenoid) in mammals
What is the dermal bone facial series?
facial series forms snout and encircles nares, includes maxilla, premaxilla, and nasals
What is the dermal orbital series?
encircles eyes and defines orbit, includes lacrimal, postorbital, and jugal (zygomatic in mammals)
What is the dermal bone temporal series?
behind orbit and forms lateral aspect of braincase, includes temporal bones, quadratojugal, and squamosal
T/F: temporal bone is a composite bone
true
petrous region and mastoid (chondrocranium), ear ossicles and styoid (splanchnocranium), and squamosal region and tympanic region (dermatocranium) are all fused into __________ bone in humans
Temporal bone
what is the dermal vault series?
roof of skull includes frontal, parietal, postparietal (lost in mammals)
what is the dermal palatal series?
roof of oral cavity includes pterygoids, vomer, palatine, parasphenoid
all may be dentigerous
