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A glomus jugulare tumor is a tumor of the part of the temporal bone in the skull that involves the middle and inner ear structures. This tumor can affect the ear, upper neck, base of the skull, and the surrounding blood vessels and nerves. A glomus jugulare tumor grows in the temporal bone of the skull, in an area called the jugular foramen.
The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal. It originates as a separate bone (tympanic bone), which in some mammals stays separate through life.
The evolution of the stapes (from the columella) was an earlier and distinct event. [36] [37] The evolution of the mammalian middle ear appears to have occurred in two steps. A partial middle ear formed by the departure of postdentary bones from the dentary, and happened independently in the ancestors of monotremes and therians. The second step ...
A bulla evolved late in time and independently numerous times in different mammalian clades, and it can be surrounded by membranes, cartilage or bone. The bulla in humans is part of the temporal bone. [7] Recently found fossils such as Morganucodon show intermediary steps of middle ear evolution.
In anatomy, the zygomatic arch, or cheek bone, is a part of the skull formed by the zygomatic process of the temporal bone (a bone extending forward from the side of the skull, over the opening of the ear) and the temporal process of the zygomatic bone (the side of the cheekbone), the two being united by an oblique suture (the zygomaticotemporal suture); [1] the tendon of the temporal muscle ...
The frontal bone is broad, the parietal bone can be expanded, and the squamous part of temporal bone is high and arched, which could all be related to increasing brain size. The sphenoid bone features a spine extending downwards, and the articular tubercle on the underside of the skull can jut out prominently as the surface behind the jaw hinge ...
The bony labyrinth (also osseous labyrinth or otic capsule) is the rigid, bony outer wall of the inner ear in the temporal bone. It consists of three parts: the vestibule, semicircular canals, and cochlea. These are cavities hollowed out of the substance of the bone, and lined by periosteum.
In two groups of early amniotes, the skull roof evolved temporal fenestrae to allow for greater movement of the jaw muscles. The two groups evolved the openings independently: The synapsids have one opening on each side, fairly low on the side of the skull, between the jugal or zygomatic bone and the elements above. Synapsids include mammals ...