TheInfoListRev V5.1.84
Xfr/
SummaryRelatedTreeNews

Related topics

Axis (anatomy)

Sponsored
Shop Amazon for mechanic tool sets
Browse products on Amazon.
Search Amazon →
As an Amazon Associate I earn from qualifying purchases.

In anatomy, the axis (from Latin axis, "axle") is the second cervical vertebra (C2) of the spine, immediately inferior to the atlas, upon which the head rests. The spinal cord passes through the axis. The defining feature of the axis is its strong bony protrusion known as the dens, which rises from the superior aspect of the bone. StructureThe body is deeper in front or in the back and is prolonged downward anteriorly to overlap the upper and front part of the third vertebra.

Cervical vertebraeCervical vertebraeIn tetrapods, cervical vertebrae (sing.: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauropsid species, the cervical vertebrae bear cervical ribs. In lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae.Atlas (anatomy)Atlas (anatomy)In anatomy, the atlas (C1) is the most superior (first) cervical vertebra of the spine and is located in the neck. The bone is named after Atlas of Greek mythology, just as Atlas bore the weight of the heavens, the first cervical vertebra supports the head. However, the term atlas was first used by the ancient Romans for the seventh cervical vertebra (C7) due to its suitability for supporting burdens.Alar ligamentAlar ligamentIn anatomy, the alar ligaments are ligaments which connect the dens (a bony protrusion on the second cervical vertebra) to tubercles on the medial side of the occipital condyle. They are short, tough, fibrous cords that attach on the skull and on the axis, and function to check side-to-side movements of the head when it is turned. Because of their function, the alar ligaments are also known as the "check ligaments of the odontoid".Apical ligament of densApical ligament of densThe apical ligament of dens (or apical odontoid ligament) is a ligament that spans between the second cervical vertebra in the neck and the skull.Occipital boneOccipital boneThe occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone lies over the occipital lobes of the cerebrum. At the base of the skull in the occipital bone, there is a large oval opening called the foramen magnum, which allows the passage of the spinal cord. Like the other cranial bones, it is classed as a flat bone.Longus colli muscleLongus colli muscleThe longus colli muscle (Latin for long muscle of the neck) is a muscle of the human body. The longus colli is situated on the anterior surface of the vertebral column, between the atlas and the third thoracic vertebra. It is broad in the middle, narrow and pointed at either end, and consists of three portions, a superior oblique, an inferior oblique, and a vertical.Spinal columnSpinal columnThe spinal column, also known as the vertebral column, spine or backbone, is the core part of the axial skeleton in vertebrates. The vertebral column is the defining and eponymous characteristic of the vertebrate. The spinal column is a segmented column of vertebrae that surrounds and protects the spinal cord. The vertebrae are separated by intervertebral discs in a series of cartilaginous joints.Transverse ligament of atlasTransverse ligament of atlasIn anatomy, the transverse ligament of the atlas is a broad, tough ligament which arches across the ring of the atlas (first cervical vertebra) posterior to the dens to keep the dens (odontoid process) in contact with the atlas. It forms the transverse component of the cruciform ligament of atlas.Spinal cordSpinal cordThe spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the lower brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals. The center of the spinal cord is hollow and contains a structure called the central canal, which contains cerebrospinal fluid. The spinal cord is also covered by the meninges and enclosed by the neural arches.AnatomyAnatomyStudy of the structure of organismsOne of the large, detailed illustrations in Andreas Vesalius's De humani corporis fabrica 16th century, marking the rebirth of anatomyAnatomy (from Ancient Greek ἀνατομή (anatomḗ) 'dissection') is the branch of morphology concerned with the study of the internal and external structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things.Human headHuman headIn human anatomy, the head is the uppermost part of the body, attached to the torso by the neck. It houses the brain, forming the cranial cavity for protection and support through the skull, which also forms the orbits and nasal cavity. The sensory organs and the mouth are part of the head. The face, except for the exposed sensory organs, is wrapped by tegument (skin, hair on the majority of the surface).

*As an Amazon Associate I earn from qualifying purchases.

AboutPrivacyContact

TheInfoList organizes topic information and links to original sources.

Loading topic…