Transcript of PowerPoint- Bajardo
- 1. Skeletal System: Skull Vhi Ann J Bajardo
- 2. Cranial Skeleton is of three parts: Vhi Ann J Bajardo
CRANIAL SKELETON Chondrocranium Splanchnocranium
Dermatocranium
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- 4. BLUE- Chondrocranium YELLOW- Splanchnocranium PINK-
Dermatocranium Vhi Ann J Bajardo
- 5. -elements found at the back of the vertebrae Nineteenth
century morphologists propose that the vertebral column is the
ancient ancestors of the chondrocranium. -neural crest cells and
mesenchyme cells differentiate to form chondrocranium Vhi Ann J
Bajardo
- 6. cos + cos = 2 cos 1 2 + cos 1 2 Vhi Ann J Bajardo
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- 8. neural crest cells contributions to the skull Vhi Ann J
Bajardo
- 9. -elements contribute to filter-feeding surfaces (Amphioxus),
jaws and hyoid apparatus (Gnathostomes) -neural crest cells arise
to form splanchnocranium Vhi Ann J Bajardo
- 10. BLUE- Chondrocranium YELLOW- Splanchnocranium PINK-
Dermatocranium Vhi Ann J Bajardo THE PARTS OF CRANIAL SKELETON
shown in FIGURE 7.1
- 11. Derivatives of Neural Crest Cells Protochordates NCC
migrate to the body wall from the neural tube NCC differentiates
into pigment cells Vertebrates NCC moves into the walls of pharynx
NCC differentiates into jaws and gill arches Vhi Ann J Bajardo
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- 13. a. ORIGIN OF JAWS -an anterior pair of gill arches gave
rise to jaws -branchial arch musculature were transformed and
modified into musculature of the jaws Divisions of mandibular arch
of jawless fishes: Neurocranium (dorsal) Mandible (ventral) Vhi Ann
J Bajardo
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- 15. Embryology of Pharyngeal Arches Protochordates Pharyngeal
arches rises from the mesoderm Most Vertebrates Pharyngeal arches
rises from neural crest cells Vhi Ann J Bajardo
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- 17. b. TYPES OF JAW ATTACHMENTS The points at which the jaws
attach to the rest of the skull defines the type of jaw attachment
Vhi Ann J Bajardo
- 18. Jaw Attachment How Jaws are Attached Vertebrates Paleostyly
no arches attach to the skull agnathans Euautostyly mandibular arch
suspended from the skull acanthodians, placoderms Amphistyly jaws
attached through ligament and hyomandibula extinct sharks,
rhipistians, osteichthyans Hyostyly mandibular arch attached
through hyomandibula modern bony fishes, extant sharks Metautostyly
jaws attached directly to braincase through quadrate amphibians,
reptiles, birds Craniostyly upper jaw incorporated to the
braincase; lower jaw suspended through dermal squamosal bone
mammals Vhi Ann J Bajardo
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- 20. -consists of dermal bones contributing the skull -forms
sides and roof of the skull -mesenchymal and ectomesenchymal
tissues of the dermis Vhi Ann J Bajardo
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- 23. Braincase- Jaws- Hyoid Apparatus- supports the tongue and
the floor of the mouth Vhi Ann J Bajardo OVERVIEW
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- 25. -movement between the upper jaw and the braincase about
joints between them Cranial kinesis: movement between the upper jaw
and braincase advantages: provides a way to change the size and
configuration of the mouth rapidly optimize biting and rapid
feeding. disadvantages: lose force, difficult to optimize
apposition of occlusive surfaces. Vhi Ann J Bajardo CRANIAL
KINESIS
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