Carbon monoxide (CO) is a colorless, odorless gas found in furnace and automobile engine exhaust and cigarette smoke. CO binds to hemoglobin 210 times more tightly than does O2. CO also binds with an electron transport protein and disrupts cellular respiration. Explain why CO is such a deadly gas.

Verified step by step guidance

1. Understand the role of hemoglobin: Hemoglobin is a protein in red blood cells responsible for transporting oxygen (O2) from the lungs to tissues and organs throughout the body. It is crucial for providing the necessary oxygen to cells for aerobic respiration, which generates energy.
2. Recognize the binding affinity of CO: Carbon monoxide (CO) binds to the iron in the hemoglobin molecule approximately 210 times more strongly than oxygen. This high affinity makes CO highly competitive against oxygen for binding sites on hemoglobin.
3. Explore the impact on oxygen transport: When CO binds to hemoglobin, it forms carboxyhemoglobin, which prevents oxygen from binding and being transported to body tissues. This leads to a decrease in the availability of oxygen in the body, causing cells to switch to anaerobic respiration, which is less efficient and produces less energy.
4. Consider the disruption of cellular respiration: CO also binds to cytochrome c oxidase, a key enzyme in the electron transport chain of mitochondria. This binding inhibits the enzyme, disrupting the electron transport chain and halting cellular respiration, which further decreases energy production in cells.
5. Summarize the lethal effects: The combined effects of impaired oxygen transport and disrupted cellular respiration lead to tissue hypoxia (lack of oxygen), cellular injury, and potentially fatal outcomes if significant exposure occurs and no intervention is made.