The sacral vertebrae is found at the base of the on the sacral bones make up the butt-bone. Thanks for asking AnswerParty!
In humans, the sacrum (plural: sacrums or sacra) is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx (tailbone). It consists of usually five initially unfused vertebrae which begin to fuse between ages 16–18 and are usually completely fused into a single bone by age 34.
It is curved upon itself and placed obliquely (that is, tilted forward). It is kyphotic—that is, concave facing forward. The base projects forward as the sacral promontory internally, and articulates with the last lumbar vertebra to form the prominent sacrovertebral angle. The central part is curved outward toward the posterior, allowing greater room for the pelvic cavity. The two lateral projections of the sacrum are called ala (wings), and articulate with the ilium at the L-shaped sacroiliac joints.
The vertebral column, also known as backbone or spine, is a bony structure found in vertebrates. It is formed from the vertebrae.
The irregular bones are bones which, from their peculiar form, cannot be grouped as long bone, short bone, flat bone or sesamoid bone. Irregular bones serve various purposes in the body, such as protection of nervous tissue (such as the vertebrae protect the spinal cord), affording multiple anchor points for skeletal muscle attachment (as with the sacrum), and maintaining pharynx and trachea support, and tongue attachment (such as the hyoid bone). They consist of cancellous tissue enclosed within a thin layer of compact bone.
The irregular bones are: the vertebræ, sacrum, coccyx, temporal, sphenoid, ethmoid, zygomatic, maxilla, mandible, palatine, inferior nasal concha, and hyoid.
The human skeleton is composed of 300 bones at birth and by the time adulthood is reached, some bones have fused together to give a total of 206 bones in the body. The bone mass in the skeleton reaches maximum density around age 30. The human skeleton can be divided into the axial skeleton and the appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage and the skull. The appendicular skeleton, which is attached to the axial skeleton, is formed by the pectoral girdles, the pelvic girdle and the bones of the upper and lower limbs.
The human skeleton serves six major functions; support, movement, protection, production of blood cells, storage of ions and endocrine regulation.
The sacral nerves are the spinal nerves which arise from the sacrum at the lower end of the vertebral column. The roots of these nerves begin inside the vertebral column at the level of the L1 vertebra and extend until the sacrum forms a structure called the cauda equina.
Colymbosaurus is a genus of English plesiosaur described in 1874 by Seeley. The only bones found include 74 vertebrae, ribs, coracoids, a scapula and fore and hind limbs (fins). This specimen may be the missing body of Kimmerosaurus, which would make this a cryptoclid instead of an elasmosaurid. Colymbosaurus may be a senior synonym of Kimmerosaurus.