Lecture 12 (Exam 2) Flashcards
Bones of the base of the skull underlie the ________ and are ________.
Brainstem
Endochondral
Bones forming the sides and roof of the skull are ________ bones and make up the bones of the ________.
Dermal
Face
________-replacement elements form in the branchial arches.
Cartilage
The ______ forms the other part of the axial skeleton (besides spinal cord).
Skull
The skull may be formed entirely of cartilage in some species like sharks, skates, and rays. Failure to replace cartilage with bone in the adult is an example of _______.
Neoteny
What 3 things may the skull be a combination of?
Cartilage
Dermal bone
Endochondral bone
In all vertebrates the brain case develops in the embryo as an incomplete cartilaginous box with numerous openings, called ________, through which pass nerves and blood vessels to and from the brain.
Foramina
Additional _________ capsules develop to enclose the special sensory organs such as the olfactory apparatus, eyes, and semicircular canals (balance).
Cartilaginous
The 2 components of the vertebral skull organization are…
Chondrocranium
Dermatocranium
The chondrocranium is subdivided into the _________ and ________. Both of these are made up of cartilage and/or endochondral bone.
Neurocranium
Splanchnocranium
The splanchnocranium is also referred to as the _________ or _________ _________.
Viscerocranium
Pharyngeal (gill) arches
The dermatocranium is made up of what?
Dermal bone
The cartilaginous embryonic skull is the _________.
Chondrocranium
The braincase, or neurocranium, makes up the mass of cartilage that condenses beneath the embryonic brain and the bones that replace this cartilage. Collectively referred to as _________.
Basicranium
The neurocranium includes three pairs of cartilaginous capsules housing special sensory organs, which are…
Olfactory
Optic
Otic
This cartilaginous capsule is the most anterior.
Olfactory
This cartilaginous capsule is the most posterior.
Otic
In the neurocranium, the floor forms two pairs of cartilaginous plates which are…
Parachordals
Perchordals (Hypophyseals)
This cartilaginous plate flanks the cranial end of the notochord.
Parachordals
This cartilaginous plate is cranial to the notochord and parachordals.
Perchordals (Hypophyseals)
The posterior wall of the neurocranium contains what?
Foramen magnum
The roof of the neurocranium is usually open, but closed in _________.
Chondrichthyes (cartilaginous fish)
The bones of the basicranium (neurocranium) represent the primitive vertebrate braincase. Therefore, all nerves and vessels passing to and from the brain pass through foraminae in these bones. The five bones are…
Ethmoid
Sphenoid
Left and right temporals
Occipital bone
This is the only basicranial bone that is entirely preformed in cartilage.
Ethmoid
What are the components (5) of the ethmoid bone?
Cribriform plate Crista galli Perpendicular plate Labyrinth Ethmoid air cells
The crista galli is the attachment for the ______ ______.
Falx cerebri