Flashcards in Anatomy- Cranial meninges, and cranial contents Deck (112)
What surrounds the brain?
what are the bones of the face called collectively?
What bones of the face come from neural crest, ectoderm?
frontal, nasal, sphenoid, lacrimal, zygomatic, maxilla, incisive, mandible, sq. temporalis, hyoid
What bones of the face come from paraxial mesoderm (somites)?
parietal, pet temporal, occipitals,
What bones are made up of lateral plate mesoderm?
The division between neural crest derives bone and paraxial mesoderm derived bone occurs at the rostral end of the notochord at the (blank)
The neural crest cells that make up the some of the bones of the skull are also the same neural crest cells that make what?
Heart and heart tube (hence why you sometimes get Craniofacial defects along with CV defects)
Is there paraxial mesoderm in front of the prechordal plate?
no, only neural crest cells
How can the neurocranium be divided?
into a membranous and cartilaginous part
What does the membranous part of the neurocranium consist of?
most of the flat bones that surround the brain (frontal, parietal, parts of temporal and occipital)
****the name membranous comes from their method of ossification i.e intramembranous******
the neurocranium develops primarily as (blank) bone
What does the cartilaginous neurocranium consist of?
How do these bones develop?
sphenoid bone, ethmoid bone, part of tempoal bone and part of occipital bone
endochondral bone ossification
Bones of the cranium arise from one source or multiple sources?
What are the exceptions to the rule that all large flat bones of the neurocranium are membranous?
part of occipital bone, part of temporal bone
(blank) develops primarily from membrane and comes from neural crest
Some parts of the viscerocranium develop from cartilaginous models.... what three bones are these?
middle ear ossicles, laryngeal cartilages and hyoid bone
Why do newborns have such small faces?
they lack teeth which results in small jaw, they have no paranasal sinuses and facial bones are underdeveloped
What are fontanelles?
6 areas where flat bones of skull meet and along with the sutrues, allow for overlap during the birthing process
Premature suture closure results in (blank)
Incomplete closure of the anterior neuropore cause the skull bones to fail to grow together and can result in (blank).
Why is it bad if you have premature suture closure as an infant?
because you limit further brain development
Please explain cranioschisis
failure of neural tube to close-> therfore failure of neurocranium to close which results in brain tissue getting exposed to amniotic fluid which degenerates and results in some type of ancephaly and the fetus is usually not viable.
What is a cranial meningoencephalocele?
The protrusion of the meninges and the brain through a congenital defect in the cranium
What is a meningocele?
the protrusion of the meninges through a congenital defect in the cranium
Is there an epidural space in the brain?
nooo... however there is a potential space
the (blank) forms the periosteum of the interior cranial cavity
Where do the meningeal arteries travel in the brain?
within the potential epidural space (i.e lies between the dura and the skull)
Why is there little grooves in the skull?
the meningeal arteries rub against the skull and erode little grooves
Why is the middle meningeal susceptible to damage?
it is superficial and located under a part of the skull that is susceptible to fracture