Lab 3: The Cranial Skeleton Flashcards
What are the main components of the cranial skeleton?
Chondrocranium
splanchnocranium
Dermatocranium
Chondrocranium
base of braincase and back of the skull. Is one piece but made up of nemerous bonds.
splanchnocranium
in the earliest jawed vertebrates the first visceral ach became___
In terapods the second visceral arch____is no longer associated with___
Arches 3-7 became ___ and are involved with
visceral arches( under nose and under the jaw… goes into the thyroid cartillage).
Develops the series of visceral arches that support gills in fish.
-became enlarged to form mandibular arch. So jaws are modified gill supports.
Manadibular arch has mandibular cartilage(lower jaw) and palatoquadrate cartilage(upper jaw)
second arch hyoid arch is no longer associared with gills but rather supports the jaw and tongue(hyoid bone)
3-7 became brachial arches involexd woith respiration
Dermatocranium
outer part of braincase(top part of brain). They developed directly within the dermal layer of the skin. Dermal bones care the orginal dermal scales
Anapsid
only yhe eye socket and nose socket in the head
synapsid
1 holes in the head
Diapsid
2 holes in the head
Example of a anapsid
turtle
example og diapsid
crocodile
Example of one temporal fossa?
dog and human
Skull modification: Secondary Plate
modifications for breathing air
Bulla?
Part of inner ear of dolphins for ecolocation
What does the cranial skeleton do?
protects the brain, sensory organs, entrance to respiratory system, and the entrance to the digestive system.
Foramina
small openings in the skull
singular= foramen
Sutures
an immovable firous joint in the skull where bone surfaces are closely united by connective tissue
