The correct answers are synapse and neurotransmitter, which makes the paragraph read as follows:
Neurons transmit signals to the central nervous system. The brain processes this information to initiate a response. Two neurons communicate with each other through the synapse. The neurotransmitter is released at the site to initiate action potential and carry the signal through the body.
The synapse is the space or junction between two nerve cells, or neurons. Neurons receive and transmit information through their axon and dendrites, respectively, but they communicate chemically with one another using chemical signals called neurotransmitters to pass a chemical signal from cell to cell and elicit a response from the body.
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