Functional Classification of Neurons

Sensory neurons transmit impulses from sensory organs to the central nervous system (CNS), detecting internal and external changes.
Interneurons are located within the CNS, processing and storing information and making decisions based on incoming sensory impulses.
Motor neurons convey messages away from the CNS to effectors, facilitating actions in response to stimuli.

The nervous system is divided into central and peripheral components.
Central Nervous System (CNS) includes the brain and spinal cord, responsible for processing information.
Peripheral Nervous System (PNS) consists of cranial and spinal nerves, connecting the CNS to the rest of the body.

Somatic Nervous System is associated with voluntary control, linking the CNS to skin and skeletal muscles.
Autonomic Nervous System regulates involuntary functions, connecting the CNS to visceral organs and consisting of sympathetic (emergency response) and parasympathetic components (rest and digest).

The spinal cord is composed of several key structures: central canal, dorsal root, dorsal root ganglion, gray matter, white matter, and ventral root.
Central Canal contains cerebrospinal fluid, providing cushioning and support.
Dorsal Root includes sensory neurons’ cell bodies and transmits sensory information to the spinal cord.
Gray Matter primarily consists of interneurons and some motor neurons; it is characterized by the absence of myelin.
White Matter, appearing white due to myelination, consists of nerve tracts that facilitate communication within the spinal cord, organized into anterior, posterior, and lateral funiculi.
Ventral Root carries axons of motor neurons that originate in the gray matter, facilitating motor control.