Which class disrupts the oxygen-carrying properties of the blood?

• A. Nerve Agents
• B. Blood Agents
• C. Blister Agents
• D. Choking Agents

Answer: (B)

The main idea here is how certain chemicals stop the body's use of oxygen. Blood agents, like cyanide compounds, block a key enzyme in cells (cytochrome c oxidase) and shut down cellular respiration. Even though oxygen is carried in the blood, the cells can’t utilize it, leading to rapid tissue hypoxia. That’s why this class is described as disrupting the oxygen-carrying properties of the blood—the oxygen is present but can’t be used effectively at the cellular level. Nerve agents affect nervous signaling, blister agents cause tissue damage, and choking agents interfere with air intake and gas exchange in the lungs. The blood-agent mechanism directly targets oxygen utilization inside cells, making it the best fit for the concept.