Final answer:
Impulses are carried from the brain to the muscles by motor nerve fibers, which are essential components of the somatic nervous system and responsible for conveying commands for voluntary muscle movements.
Step-by-step explanation:
Impulses are carried from the brain to the muscles by motor nerve fibers. These nerve fibers, which are part of the nervous system, are also known as efferent neurons.
Motor neurons are responsible for carrying instructions from the central nervous system (CNS) directly to the muscles, leading to muscle activation. This is different from sensory neurons, or afferent neurons, which carry information from sensory receptors to the CNS.
The somatic nervous system is a part of the peripheral nervous system that is associated with voluntary control of body movements via skeletal muscles, and these motor fibers play a crucial role in this system.