SHARK: AXIAL SKELETON: SKULL CHONDROCRANIUM Flashcards
part of the skull consists of a single irregularly shaped cartilaginous mass, which encloses the brain
NEUROCRANIUM
scoop-like anterior projection of the chondrocranium enclosing the precerebral cavity, and is filled with gelatinous material
ROSTRUM
the rostrum encloses the
precerebral cavity
two large apertures at the base of the rostrum
rostral fenestrae
rounded swellings located on either side of the base of the rostrum; thin walls are readily damaged during preparations and thus may be found to be incomplete
OLFACTORY CAPSULES
Located on both sides of the neurocranium
ORBITS
the anterior limit of the orbit is demarcated by
antorbital process
the antorbital process continues backward as the
supraorbital crest
the supraorbital crest continues backward as the
supraorbital crest
the supraorbital crest terminates as the
postorbital process
irregularly shaped masses, protecting the ear that are fused posteriorly to the neurocranium
otic capsule
otic capsule is bounded dorsolaterally by ______________, which is a backward continuation of the postorbital process
supraotic crest
located in the median line, just behind the precerebral cavity; It is where the stalk-like epiphysis (pineal organ) passes through
EPIPHYSEAL FORAMEN
A large deep depression located in the median in region of the otic capsules; it conatins a pair of small anterior ___________ and a pair of larger
ENDOLYMPHATIC FORAMINA
POSTERIOR PERILYMPHATIC FORAMINA
Keel-shaped structure located on the midventral surface of the rostrum
ROSTRAL CARINA
Ridge that demarcates the anterior boundary of the orbit
ANTORBITAL SHELF
Portion of the floor of the chondrocranium shelf, and extends back as median ridge from the antorbital shelves
INFRAORBITAL SHELF
Expanded posterior part of the neurocranium extending back from the infraorbital shelf
BASAL PLATE
located in the median line at the junction of the infraorbital shelf and basal plate
CAROTID FORAMEN
ring-shaped process located at each posterolateral corner of the ventral surface of the chondrocranium
POSTOTIC PROCESS
Openings of the postotic process
POSTOTIC FENESTRAE
definite structure on the lateral side of the chondrocranium
OPTIC PEDICEL
a large opening, located antero-ventrally in the orbit, that provides passage for the optic nerve (N.II)
OPTIC FORAMEN
located just above the root of the optic pedicel; it is the opening through which the oculomotor nerve (N. III) gains entrance into the orbit
OCULOMOTOR FORAMEN
A small anterodorsally located opening that lies a short distance above the optic foramen. The trochlear nerve (N. IV) emerges into the orbit through it.
TROCHLEAR FORAMEN
A series of small openings located parallel to and a little below the supraorbital crest. Can be seen on the dorsal side of the chondrocranium. Through them passes the trigeminal (N.V) and facial nerves (N. VII)
SUPERFICIAL OPTHALMIC FORAMINA
located just in front of the most anterior superficial ophthalmic foramina; a branch of trigeminal nerve passes into the orbit through this foramen
DEEP OPTHALMIC FORAMINA
A large foramen located at the posterior border of the orbit behind the optic pedicel. It is where the main branches of the trigeminal and facial nerves pass through. ALSO KNOWN AS THE ORBITAL TISSUE
TRIGEMINOFACIAL FORAMEN
Located in the otic capsule slightly behind the trigeminofacial foramen. It is where the hyomandibular nerve pass through
HYOMANDIBULAR FORAMEN
large median opening through which the spinal cord passes
FORAMEN MAGNUM
Processes located ventro-laterally on either side of the foramen magnum that articulate with the first trunk vertebra
OCCIPITAL CONDYLES
A pair of openings located laterally on each side of the occipital condyles. The vagus (N. X) nerve passes through each
VAGUS FORAMINA
located near the posterolateral corners of the chondrocranium. The glossopharyngeal nerve (N. IX) pass through them.
GLOSSOPHARYNGEAL FORAMINA
