AEMCA Practice Exam

How do nerve agents affect the body?

1. By stimulating the production of serotonin

2. By disrupting the enzyme acetylcholinesterase

3. By increasing the amount of blood oxygen

4. By blocking nerve signals completely

The correct answer is: By disrupting the enzyme acetylcholinesterase

Nerve agents primarily affect the body by disrupting the enzyme acetylcholinesterase. This enzyme is crucial for breaking down acetylcholine, a neurotransmitter that plays a significant role in transmitting nerve impulses in the body. When acetylcholinesterase is inhibited, acetylcholine accumulates at synapses, leading to overstimulation of muscles and other tissues. This can cause symptoms such as muscle spasms, paralysis, and potentially death due to respiratory failure. The other options are not accurate representations of the effects of nerve agents. For instance, the production of serotonin is not directly related to nerve agents; instead, it pertains to mood regulation and various physiological functions. The claim about increasing blood oxygen does not relate to the mechanism of action of nerve agents, which impair the body’s ability to function normally rather than enhance oxygen levels in the blood. Finally, while nerve agents can indeed cause problems with nerve signals, they do not completely block them; rather, they create a state of excessive stimulation. Therefore, the action of nerve agents is specifically linked to the disruption of acetylcholinesterase, leading to harmful physiological effects.