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Why is the sphenoid bone called the keystone of the cranial floor?
Wiki User
∙ 13y ago
Sphenoid bone: A prominent, irregular, wedge-shaped bone at the base of the skull. The sphenoid bone has been called the "keystone" of the cranial floor since it is in contact with all of the other cranial bones.
The Greek physician Galen wrote that the sphenoid bone was "like a wedge thrust between the skull and the superior maxilla."
Wiki User
∙ 14y ago
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Which cranial bone spans the width of the cranial floor?
Sphenoid bone
What cranial bone articulates with all other cranial bones?
The Sphenoid (Sphenoidal Bone) this is why it is know as the keystone of the cranial floor *The sphenoid is not a facial bone, it is a cranial bone. There is no facial bone which 'articulates' with 'every other facial bone'. Articulation suggests jointed so sutures would make more sense & these sutures would be on all facial bones edges which knit them together
What is the cranial floor?
If you were to do a horizontal section of skull and look down into the cavity you would see a base made up of three levels. This is where the cerebrum sits and is called the cranial floor.
What bone is located at the base of the skull?
There are two joints at the base of the skull: - a condyloid joint between the occipital bone of the skull and the first (C1) vertebra, the atlas. - a pivot joint located between the C1 and C2 cervical vertebrae (atlas and axis).
Name the bones that compose the orbit of the eye?
The bones that form the orbit of the eye are the ethmoid, lacrimal, maxilla, frontal, sphenoid, zygoma, palatine The orbits are pyramidal, bony cavities in the facial skeleton with their bases (orbital openings) directed anterolaterally and their apices, posteromedially. The orbits contain and protect the eyeballs and their muscles, nerves, and vessels, together with most of the lacrimal apparatus. All space in the orbits not occupied by structures is filled with orbital fat. The fat forms a matrix in which the structures of the orbit are embedded. The orbit has a base, four walls, and an apex: The superior wall (roof) is approximately horizontal and is formed mainly by the orbital part of the frontal bone, which separates the orbital cavity from the anterior cranial fossa. Near the apex of the orbit, the superior wall is formed by the lesser wing of the sphenoid. Anterolaterally the lacrimal gland occupies the fossa for the lacrimal gland (lacrimal fossa) in the orbital part of the frontal bone. The medial wall is formed by the ethmoid bone, along with contributions from the frontal, lacrimal, and sphenoid bones. Anteriorly, the medial wall is indented by the lacrimal groove and fossa for the lacrimal sac. The bone forming the medial wall is paper thin, and the ethmoid air cells are often visible through the bone of a dried cranium. The lateral wall is formed by the frontal process of the zygomatic bone and the greater wing of the sphenoid. This is the strongest and thickest wall, which is important because it is most exposed and vulnerable to direct trauma. Its posterior part separates the orbit from the temporal lobes of the brain and middle cranial fossae. The inferior wall (floor) is formed mainly by the maxilla and partly by the zygomatic and palatine bones. The thin inferior wall is shared by the orbit superiorly and the maxillary sinus inferiorly. It slants inferiorly from the apex to the inferior orbital margin. The inferior wall is demarcated from the lateral wall by the inferior orbital fissure. The apex of the orbit is at the optic canal in the lesser wing of the sphenoid, just medial to the superior orbital fissure. The bones forming the orbit are lined with periorbita (periosteum of the orbit). The periorbita is continuous at the optic canal and superior orbital fissure with the periosteal layer of dura mater. The periorbita is also continuous over the orbital margins and through the inferior orbital fissure with the periosteum covering the external surface of the cranium (pericranium) and with the orbital septa at the orbital margins, with the fascial sheaths of the extraocular muscles, and with orbital fascia that forms the fascial sheath of the eyeball.
Single irregular bat-shaped bone forming part of the cranial floor?
It is a sphenoid bone; single, irregular bat(a bird)-shape bone forming part of the CRANIAL Floor. Not many people think sphenoid bone being part of the cranial bone that is why they don't find any answer to this question. but Sphenoid bone is one of the cranial bone and can be found on the cranial floor when looking at the skull from its superior view.
Which cranial bone spans the width of the cranial floor?
Sphenoid bone
What cranial bone articulates with all other cranial bones?
The Sphenoid (Sphenoidal Bone) this is why it is know as the keystone of the cranial floor *The sphenoid is not a facial bone, it is a cranial bone. There is no facial bone which 'articulates' with 'every other facial bone'. Articulation suggests jointed so sutures would make more sense & these sutures would be on all facial bones edges which knit them together
What bony depression of the cranial floor does the pituitary sit?
sella turcica of the sphenoid bone
What bone is single irregular bat shaped forming part of the cranial floor?
hyoid That is incorrect. The Sphenoid Bone is Bat-Shaped. The Hyoid bone is considered Horseshoe-shaped
What is the cranial floor?
If you were to do a horizontal section of skull and look down into the cavity you would see a base made up of three levels. This is where the cerebrum sits and is called the cranial floor.
Which bone is the central part of the floor of the cranium and the location of the pituitary gland?
Sphenoid
Single irregular bat shaped bone forming part of craniel floor?
Sphenoid Bone
What bone is at the base of the skull?
occipital boneocciputOccipital boneThe bone is called the occipital bone which forms most of the skulls posterior wall and base. It articulates with anteriorly with the paried parietal and temporal bones via the lambdoid and occipitomastoid stures. It also joins the sphenoid bone in the cranial floor.
What bone is located at the base of the skull?
There are two joints at the base of the skull: - a condyloid joint between the occipital bone of the skull and the first (C1) vertebra, the atlas. - a pivot joint located between the C1 and C2 cervical vertebrae (atlas and axis).
What is the bone located between the eyes that extends into the nasal cavity eye sockets and cranial floor is called what?
ethmoid bone... have fun wth your WSJ puzzle!
What nerve is used for mastication in dobermans?
The cranial nerve responsible for moving the cheek muscles is cranial nerve V (the trigeminal nerve). However, cranial nerve IX (glossopharyngeal) and cranial nerve XII (hypoglossal) are also involved in moving the tongue, the throat for swallowing and the muscles along the floor of the jaw.
