The gustatory cortex, involved in the perception of taste, is located in the:

Correct Answer: C

Rationale: The gustatory cortex, often in the insular/temporal region, processes taste.

Correct Answer: A

Rationale: The cervical plexus arises from C1-C4, serving neck and diaphragm.

Correct Answer: B

Rationale: Glutamic acid (glutamate) is the primary excitatory neurotransmitter in the CNS. Leucine, lysine, and valine are not neurotransmitters.

Correct Answer: C

Rationale: Tetrodotoxin (from pufferfish) blocks voltage-gated Na+ channels, halting action potentials. Strychnine blocks glycine, neostigmine inhibits acetylcholinesterase, curare blocks nicotinic receptors.

Correct Answer: B

Rationale: The dorsal root ganglion (DRG) houses the cell bodies of sensory neurons, adjacent to the spinal cord. The dorsal gray horn processes sensory signals, the spinal cord is a broader structure, and the brain is not the site for sensory neuron cell bodies.