Final answer:
The human spinal cord consists of gray matter (cell bodies and interneurons) and white matter (myelinated axons), with posterior, anterior, and lateral horns and columns. It transmits sensory and motor information between the body and brain via spinal nerves.
Step-by-step explanation:
Components of the Human Spinal Cord
The human spinal cord is a crucial part of the central nervous system, connecting to the brainstem and extending through the spinal column to the pelvis. It serves as a conduit for information between the body and the brain. The spinal cord is comprised of gray matter and white matter. The gray matter, which appears like a butterfly in cross-section, contains the cell bodies of neurons, including interneurons and motor neurons. The white matter consists mainly of myelinated axons that facilitate the transmission of signals. Spinal nerves, which are part of the peripheral nervous system, exit from the spinal cord between the vertebrae. These nerves are crucial for conveying sensory information to the brain and motor commands back to the body.
A cross-section of the spinal cord reveals the posterior, anterior, and lateral horns of gray matter, as well as the posterior, anterior, and lateral columns of white matter. The anterior median fissure and the posterior median sulcus are surface features that mark the spinal cord's midlines. Sensory information enters the spinal cord through the dorsal nerve roots, while motor signals exit through the ventral nerve roots.