Bio 204- skulls
1. Chondrocranium:: Forms as cartilage in embryo
Teleostomi adults: endochondral bone and cartilage.
Agnatha and Chondrichyes: cartilage
2. Splanchnocranium: - mandibular Arch, Hyoid Arch, other branchial arches
- Forms as cartilage in embryo
- Teleostomi adults: endochondral bone and cartilage.
-Agnatha and Chondrichyes: cartilage
- The splanchnocranium forms the pharyngeal arches and their derivatives. Typically, the splanchnocranium forms seven
arches: pharyngeal arches I - VII.
3. Dermatocranium:: Forms as bone in embryo
Teleostomi adults: dermal bone.
4. Braincase: Agnatha and chondrichthyes? Teleostomi?: Region of the skull that immedi-
ately surrounds the brain.
Agnatha and chondrichthyes: Braincase is chondrocranium
Teleostomi: the chondrocranium forms the ventral region of braincase while dermatocranium forms the dorsal region.
5. In many gnathostomes, the mandibular arch forms the:: In many gnathostomes, the
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, mandibular arch forms the: jaws (or parts of the jaws).
6. In some gnathostomes, the hyomandibula of the hyoid arch is used for:: In
some gnathostomes, the hyomandibula of the hyoid arch is used for: jaw suspension - attaching the jaws to the rest
of the skull
7. Branchial arches:: In many fish (and larval amphibians), pharyngeal arches III-VII form the branchial arches,
which support the gills and also serve as attachment sites for some respiratory muscles (such as many of the muscles
of the muscular pharyngeal pump).
8. In chondrichthyes, the jaws are formed entirely from:: The palatoquadrate (upper jaw)
and Meckel's cartilage (lower jaw) of the splanchnocranium.
9. In most teleostomi, the jaws are formed from both bones of the:: dermatocranium
(e.g. the premaxilla and maxilla of the upper jaw) and the splanchnocranium (e.g. quadrate and articular bones).
10. Evidence for homology in skull:: Information on which component of the skull, and which specific
region of that component, gives rise to a given structure of the skull in one vertebrate taxon can be used to provide
evidence for whether or not it is homologous to a structure of the skull in a different vertebrate taxon.
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1. Chondrocranium:: Forms as cartilage in embryo
Teleostomi adults: endochondral bone and cartilage.
Agnatha and Chondrichyes: cartilage
2. Splanchnocranium: - mandibular Arch, Hyoid Arch, other branchial arches
- Forms as cartilage in embryo
- Teleostomi adults: endochondral bone and cartilage.
-Agnatha and Chondrichyes: cartilage
- The splanchnocranium forms the pharyngeal arches and their derivatives. Typically, the splanchnocranium forms seven
arches: pharyngeal arches I - VII.
3. Dermatocranium:: Forms as bone in embryo
Teleostomi adults: dermal bone.
4. Braincase: Agnatha and chondrichthyes? Teleostomi?: Region of the skull that immedi-
ately surrounds the brain.
Agnatha and chondrichthyes: Braincase is chondrocranium
Teleostomi: the chondrocranium forms the ventral region of braincase while dermatocranium forms the dorsal region.
5. In many gnathostomes, the mandibular arch forms the:: In many gnathostomes, the
1/8
, mandibular arch forms the: jaws (or parts of the jaws).
6. In some gnathostomes, the hyomandibula of the hyoid arch is used for:: In
some gnathostomes, the hyomandibula of the hyoid arch is used for: jaw suspension - attaching the jaws to the rest
of the skull
7. Branchial arches:: In many fish (and larval amphibians), pharyngeal arches III-VII form the branchial arches,
which support the gills and also serve as attachment sites for some respiratory muscles (such as many of the muscles
of the muscular pharyngeal pump).
8. In chondrichthyes, the jaws are formed entirely from:: The palatoquadrate (upper jaw)
and Meckel's cartilage (lower jaw) of the splanchnocranium.
9. In most teleostomi, the jaws are formed from both bones of the:: dermatocranium
(e.g. the premaxilla and maxilla of the upper jaw) and the splanchnocranium (e.g. quadrate and articular bones).
10. Evidence for homology in skull:: Information on which component of the skull, and which specific
region of that component, gives rise to a given structure of the skull in one vertebrate taxon can be used to provide
evidence for whether or not it is homologous to a structure of the skull in a different vertebrate taxon.
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