| Anterior Spinal Artery | The artery running along the front of the spinal cord, supplying the anterior two-thirds of the structure with blood. Originates from branches of the vertebral arteries. |
| Anterior Spinal Vein | Vein running alongside the anterior spinal artery, involved in the venous drainage of the spinal cord. |
| Arachnoid Villi | Small protrusions of the arachnoid membrane into the dural venous sinuses, allowing cerebrospinal fluid (CSF) to exit the subarachnoid space and enter the bloodstream. |
| Cauda Equina | A bundle of spinal nerve roots arising from the lower end of the spinal cord and extending downwards within the vertebral canal, resembling a horse's tail. |
| Central Canal | A narrow channel running the length of the spinal cord within the gray matter, filled with cerebrospinal fluid (CSF). |
| Chemoreceptor Trigger Zone (CTZ) | Located in the brain's area postrema, it is sensitive to blood-borne drugs or hormones and can activate the vomiting center. Contains receptors for serotonin, neurokinin, and dopamine. |
| Dorsal Root | A branch of a spinal nerve that carries sensory information from the peripheral nervous system to the spinal cord. |
| Epidural Space | The space outside the dura mater but inside the bony structure of the vertebral column, containing fat and small blood vessels. Clinically important for the administration of epidural anesthesia. |
| Intervertebral Disc | The cartilaginous pad located between the vertebrae of the spine, serving as a shock absorber and allowing flexibility. |
| Nucleus Pulposus | The inner gel-like core of an intervertebral disc, which gives the disc its elastic shock-absorbing properties. |
| Posterior Spinal Arteries | Typically paired arteries that run along the dorsal (back) surface of the spinal cord, supplying the remaining one-third of the cord, including the posterior columns. Originate from the vertebral arteries or the posterior inferior cerebellar artery. |
| Radicular Arteries | Small vessels branching off segmentally from vertebral or deep cervical arteries, penetrating the dura mater to supply the nerve roots and contribute to the blood supply of the spinal cord. |
| Subarachnoid Space | The fluid-filled space surrounding the brain and spinal cord, where cerebrospinal fluid (CSF) circulates, acting as a cushion to protect the central nervous system. |
| Vomiting Center | The brain section with receptors for neurotransmitters such as serotonin, neurokinin, and dopamine, which, when activated, can initiate the vomiting reflex. Located in the medulla oblongata and coordinates the act of vomiting by integrating various bodily responses. |
