The blanks in the question can be filled with the following words in the order listed:
1. Sensory receptors.
2. Sensory neurons.
3. Peripheral nervous system.
4. Central nervous system.
5. Interneuron.
6. Motor neurons.
The brain is the major organ of interpretation in the body, all the stimuli received by the body is sent to it for proper interpretation and response. When the body receive a stimuli, it sent it to the central nervous system for interpretation through sensory neurons, the brain receive the message, interpret it and send back appropriate response via the motor neurons.