How does CO harm us?

Explanation

**Step-by-Step Solution:**

1. **Understanding Carbon Monoxide (CO):** Carbon monoxide is a colorless, odorless gas that can be harmful when inhaled. It is produced by burning fossil fuels and can accumulate in enclosed spaces.

2. **Role of Hemoglobin:** In our blood, there is a red pigment called hemoglobin. Hemoglobin's primary function is to transport oxygen from the lungs to the rest of the body.

3. **CO's Interaction with Hemoglobin:** When carbon monoxide is inhaled, it binds with hemoglobin more effectively than oxygen does. This means that CO can occupy the sites on hemoglobin that are meant for oxygen.

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