Spinal Cord
The spinal cord is a crucial part of the central nervous system (CNS) and plays a vital role in transmitting signals between the brain and the rest of the body. It is a long, tubular structure that extends from the base of the brain (at the level of the medulla oblongata) to the lower back. The spinal cord is protected by the bony vertebral column, which consists of individual vertebrae. The spinal cord is a vital component of the nervous system, facilitating communication between the brain and the rest of the body. Its structure and function are essential for sensory perception, motor control, and reflex actions. Injuries or diseases affecting the spinal cord can have significant implications for neurological function. Spinal cord is a cylindrical structure that runs through the center of your spine, from your brainstem to your low back.
- Length : The spinal cord is approximately 16 to 18 inches long in adults.
- Segments : It is divided into segments, each corresponding to a specific region of the body. There are cervical, thoracic, lumbar, sacral, and coccygeal segments.
- Gray Matter and White Matter : The spinal cord consists of both gray matter and white matter. The gray matter contains nerve cell bodies, while the white matter consists of nerve fibers (axons) that transmit signals.
- Dorsal and Ventral Horns : Gray matter is organized into dorsal and ventral horns. The dorsal horns receive sensory input, while the ventral horns send motor signals.
- Central Canal : A small canal runs through the center of the spinal cord, containing cerebrospinal fluid (CSF).
- Transmission of Signals : The spinal cord acts as a relay center, transmitting signals between the brain and the peripheral nervous system. Sensory information from the body is conveyed to the brain, and motor commands are sent from the brain to muscles and glands.
- Reflexes : The spinal cord is responsible for coordinating reflex actions. Reflexes are rapid, involuntary responses to stimuli that do not require conscious thought.
- Pairs of Nerves : At each spinal level, pairs of spinal nerves emerge from the spinal cord. There are 31 pairs of spinal nerves in humans.
- Vertebral Column : The spinal cord is surrounded and protected by the vertebral column, which is composed of stacked vertebrae.