Final answer:
Carbon monoxide is toxic due to its strong affinity for hemoglobin, leading to a decrease in oxygen affinity, the formation of carboxyhemoglobin, and tissue hypoxia.
Step-by-step explanation:
Carbon monoxide is toxic because it has a greater affinity for hemoglobin than oxygen, resulting in it binding more strongly to hemoglobin than oxygen. This leads to a decrease in the oxygen affinity of hemoglobin and the formation of carboxyhemoglobin, where carbon monoxide binds to hemoglobin instead of oxygen. As a result, very little oxygen can be transported through the body, causing tissue hypoxia. Carbon monoxide is a colorless, odorless gas that is difficult to detect and can cause symptoms such as headaches, confusion, and nausea. Long-term exposure to carbon monoxide can even lead to brain damage or death.