Which type of nerve fibers carry impulses from the brain or spinal cord to muscles, organs, or glands?

• A. Motor (Efferent) Nerve
• B. Sensory (Afferent) Nerve
• C. Interneuron
• D. Mixed Nerve

Answer: (A)

The key idea is direction of signals. Impulses that leave the brain or spinal cord to act on the body are carried by motor (efferent) fibers. These nerves transmit commands to effectors—skeletal muscles to produce movement, or glands and organs to regulate function—so they’re responsible for actions initiated by the CNS. Sensory (afferent) nerves, in contrast, bring information from the body to the CNS. Interneurons stay within the CNS to connect other neurons, and mixed nerves contain both motor and sensory fibers but aren’t defined by carrying signals away from the CNS to effectors. So, for impulses traveling from the CNS to muscles, organs, or glands, motor (efferent) nerves are the correct type.