This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Physiology
[{'content': 'All of the following act as gaseous neurotransmitters except \nSelect and explain. \nA. Oxygen, B. Carbon monoxide, C. Nitric oxide, D. H2S', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) Oxygen # TYPES OF NEUROTRANSMITTERS:> There are many different ways to classify neurotransmitters. Dividing them into amino acids, peptides, and monoamines is sufficient for some classification purposes.> Major neurotransmitters:> Amino acids: glutamate, aspartate, D-serine, Gamma-aminobutyric acid (GABA), glycine> Monoamines and other biogenic amines: dopamine (DA), norepinephrine (noradrenaline; NE, NA), epinephrine (adrenaline), histamine, serotonin (SE, 5-HT)> Peptides: somatostatin, substance P, opioid peptides> Others: acetylcholine (ACh), adenosine, anandamide, nitric oxide, etc..', 'role': 'assistant'}]