Bio 290: Intervertebral Joints & Ligaments

The xiphoid process is the most inferior, narrow, triangular shaped section of the sternum. It is located at the bottom of the sternum and is made of cartilage. It serves as an attachment point for various muscles and ligaments in the abdomen. The xiphoid process is the smallest and most fragile part of the sternum and can sometimes be easily fractured or injured.

Intervertebral disks are located between the vertebral bodies and serve two main functions. Firstly, they form joints between the vertebral bodies, allowing for movement and flexibility in the vertebral column. Secondly, they act as shock absorbers, cushioning and distributing the forces that are applied to the spine during activities such as walking, running, or jumping. Therefore, the statement that intervertebral disks both form joints between vertebral bodies and act as shock absorbers for the vertebral column is true.

Herniated disks most commonly occur in the lumbar region because it is the area where the stress on the vertebral column is the greatest. The lumbar region is located in the lower back and supports a significant amount of weight and movement, making it more prone to injury and disk herniation. The sacral and coccygeal regions are lower down the spine and do not experience as much stress, making them less likely locations for herniated disks.

The second section of the sternum is known as the body. The sternum is divided into three sections: the manubrium, the body, and the xiphoid process. The body is the middle and largest section of the sternum, located between the manubrium and the xiphoid process. It is elongated and forms the main part of the sternum.

Intervertebral disks are composed of two features: an elastic nucleus pulposus and an anulus fibrosus. The elastic nucleus pulposus is a soft, gel-like substance located in the center of the disk, which provides cushioning and shock absorption for the spine. The anulus fibrosus, on the other hand, is a tough, fibrous outer layer that surrounds and protects the nucleus pulposus. Together, these two features help to maintain the structural integrity of the intervertebral disk and allow for flexibility and movement of the spine.

The sternum is indeed located in the midline of the anterior body wall of the thorax. It is a long flat bone that connects to the ribs and forms the front of the rib cage. The sternum is divided into three parts: the manubrium, the body, and the xiphoid process. This division allows for flexibility and movement of the rib cage during breathing. Therefore, the statement is true.

The most superior part of the sternum is called the manubrium. It is a broad, triangular-shaped bone that forms the upper portion of the sternum. The manubrium is located at the base of the neck and articulates with the clavicles and the first pair of ribs. It provides attachment sites for various muscles and ligaments, and serves as an important landmark in the chest anatomy.

The supraspinous ligament connects the tips of the spinous processes of the vertebrae in the cervical spine, not the skull.

The supraspinous ligament is a strong fibrous band that connects the posterior spinous processes of the vertebrae. This ligament provides stability and support to the spinal column, helping to maintain proper alignment of the vertebrae. Therefore, it is true that the supraspinous ligament attaches the posterior spinous processes to each other.

The head of the rib has two articular facets that form joints with the vertebral bodies of two thoracic vertebrae.

Ribs are only found in the thoracic part of the trunk.

The correct answer is "neck" or "Neck". The explanation is that the neck of the rib is the part that lies between the head and the tubercle.

The ligament that is attached to the skull and cervical spinous processes is the nuchal ligament. The nuchal ligament is a strong, elastic ligament that runs along the back of the neck and provides support for the head. It helps to maintain the upright position of the head and also assists in stabilizing the cervical spine.

Ribs 8-10 attach indirectly to the sternum via costal cartilages of the more superior ribs. Ribs 11-12 are the two floating ribs lacking attachment.

The correct answer is "tubercle". The tubercle of the rib is located on the posterior surface and it has a facet that allows it to articulate with a thoracic transverse process.

The correct answer is "angle". The question is asking about the location of the shaft of the rib just beyond the tubercle. The word "angle" suggests that the shaft runs sharply and anteriorly at a specific point. This is supported by the mention of intercostal nerves and blood vessels being located in the costal groove along the inferior and medial surface of the rib shaft, indicating a specific angle or direction of the rib shaft.

The Nucleus pulposus protrudes through the annulus fibrosus.

The word "shaft" refers to the long, narrow, and cylindrical portion of an object. In the context of the question, it is referring to the rib. The rib is described as curved, thin, and flat, which aligns with the characteristics of a shaft. Therefore, "shaft" is the correct answer.