unit 5 Flashcards
what is the skull comprised of
chondocranium, splanchnocranium, dermatocranium
axial skeleton is made of
vertebral column, notochord, ribs, sternum
appendicular skeleton is made of
paired fins or limbs, girdles
embryonic orgin of chondocranium
mesenchyme and neural crest cells
embryonic orgin of splanchnocranium
neural crest cells
embryonic orgin of dermatocranium
mesenchyme of the dermis
brain case of agnatha and chondrichthyes
chondocranium forms the entire braincase
braincase of teleostomi
chondocranium forms the ventral region of the braincase and the dermatocranium forms the dorsal region
what forms the pharyngeal arches and their derivatives
splanchnocranium
gnathostomes jaw and jaw suspension
mandibular arch forms the jaws and in some gnathostomes the hyomandibula of the hyoid arch is used for jaw suspension
pharyngeal arches 3-7 in fish and amphibians
form branchial arches that support the gills and are attachment sites for some respiratory muscles
chondrichthyes jaw and meckles cartiledge formation
jaw from palatoquadrate and meckles cartiledge from splanchnocranium
teleostomi jaws, quadrate and articular bones
jaws: dermatocranium
quadrate and articular bones: splanchnocranium
prehension
grasping and holding prey, swallowing them whole
durophagy
use a powerful bite to crush hard food items
mastication
rhythmic and repetitive movements of the jaw that grind food
suction feeding
rapid expansion of the buccal cavity and pharynx generates a sudden decrease in pressure that sucks prey into the mouth
akinetic skull
one pair of mobile joints, joint between upper and lower jaw. only lower jaw is mobile
kinetic skull
movement of upper jaw relative to the braincase. requires at least one mobile joint between the braincase and some element of the upper jaw
paleostyly
habing no jaw. this was true for agnathans. in this case the pharyngeal arches of the splanchnocranium support the gills
autostyly
palatoquadrate was attached directly and firmly to the brain case. hyoid arch is not involved in the jaw suspension. common in holocephali
hyostyly
palatoquadrate does not attach directly to the braincase. jaws are suspended from the braincase by hyomandibula. mobile joint between hyomandibula and braincase and between the hyomandibula jaws. allows the jaw to protrude. true for most elasmobranchii.
what does hyostyly do for elasmobranchii
allows the mouth to open wider and close faster. this allows upper and lower jaws to strike the prey at the same time allowing the shark to grip the prey secureley
what type of jaw suspension do actinopterygii have
modified hyostylic jaw suspension. main attachment of the jaws to the braincase is by the hyoid arch espeically the hyomandibula. kinetic jaw suspension.
in actinopterygii how is the mobile joint between the upper and lower jaw formed
formed by the quadrate bone of the upper jaw and the articular bone of the lower jaw
what type of feeding do actinopterygii have
suction feeding
how many mobile joints do actinopterygii have
- maxilla and chondocranium, premaxilla and chondocranium, maxilla and premaxilla
in actinopterygii how is the hyoid apparatus formed and what does it support
formed by ventral elements of the hyoid arch and other pharyngeal arches. supports the tongue and the loor of the mouth
what are actinopterygii second jaws made of
pharyngeal jaws are made of modified elements of the posterior pharyngeal arches.
what type of jaw suspension do amphibians and sauropsids have
metautostyly. jaws are attached to the braincase directly by the quadrate bone of the upper jaw
do amphibians and sauropsids have a hyomandibula
no. it is reduced to the columella in the middle ear
what do aves and lepidosauria have for jaw suspension
metautostyly with streptostyly
what is metautostyly with strepostyly
quadrate forms a swinging bridge allowing the lower jaw to protrude increasing the range of motion of the lower jaw
what type of jaw suspension do mammals have
craniostylic jaw suspension
what is craniostylic jaw suspension
entire upper jaw attaches firmly to the braincase. both upper and lower jaws are formed completely from dermatocranium
transcranial joint locations
metakinesis: (near the back (posterior) of the skull)
mesokinesis: just posterior to the eyes
prokinesis: anterior to the eyes
what type of transcranial joint does lepidosauria have
mesokinesis
what type of jaw suspension does aves have
streptostylic jaw suspension
do crocdillia have kinetic or akinetic skulls
akinetic
what does the primary palate do
separate the brain from the oral passage or nasal passage.
what does secondary palate do
separates the oral pasage from the nasal passage. can be made of bone, soft fleshy tissue, or a combo
which taxa do not have secondary palate
fish, amphibia, and most lepidosauria
do tetsudinata have a partial bondy secondary palate
most yes
what taxa are classified as being anapsid, synapsid, or diapsid
amniotes
3 types of locations of temporal fenestrae
anapsid (temporal fenestrae and orbit are fused as one big hole)
synapsid (one fenestraw posterior to the orbit)
diapsid (2 fenestrae, one is anterior and ventral to the orbit, the other is anterior and dorsal to the orbit)
t/f lepidosauria and archosauria have diapsid skulls
true
