AP BIOLOGY

Detailed explanation-1: -A motor neuron is a nerve cell that transmits impulses from the brain or spinal cord to a muscle or gland. A relay neuron connects sensory and motor neurons and is found in the brain or spinal cord (see diagrams 14.1 and 14.2).

Detailed explanation-2: -The nervous system uses tiny cells called neurons (NEW-ronz) to send messages back and forth from the brain, through the spinal cord, to the nerves throughout the body. Billions of neurons work together to create a communication network. Different neurons have different jobs.

Detailed explanation-3: -Motor or efferent neurons transmit impulses from the central nervous system towards the effectors (muscle or glands), while sensory neurons transmit impulses from the sense organs towards the central nervous system (brain and spinal cord).