THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The spinal cord expansion that corresponds to the arms is called the cervical enlargement and includes spinal segments C5-T1; the expansion that corresponds to the legs is called the lumbar enlargement and includes spinal segments L2-S3.

Detailed explanation-2: -The cervical spine (neck region) consists of seven bones (C1-C7 vertebrae), which are separated from one another by intervertebral discs. These discs allow the spine to move freely and act as shock absorbers during activity.

Detailed explanation-3: -The brachial plexus is a major network of nerves transmitting signals responsible for motor and sensory innervation of the upper extremities, including the shoulder, arm, and hand. It originates from the ventral rami of C5 through T1 spinal nerves.

Detailed explanation-4: -The cervical (neck) and lumbar (lower back) segments house the spinal cord’s two areas of enlargement. A fibrous band called the filum terminale begins at the tip of the conus medullaris and extends to the pelvis.