Answer:
1. Receptor: where stimulus action is.
2. Sensory Neuron: responsible of transmitting afferent impulses to the central nervous system.
3. Integration Center: Sensory impulse to motor impulse; Direct (monosynaptic) or polysynaptic region in CNS.
4. Motor Neuron: Efferent impulses from integration center to effector.
5. Effector: Muscle fiber or gland cell that responds to the efferent impulses.
B. receptor, sensory, interneuron, motor, effector