Which of the following gases reacts with the haemoglobin in blood? 

CO

The correct answer is option 1. CO.

Carbon monoxide (CO) is a colorless and odorless gas that can have severe health effects when inhaled. It is particularly dangerous because it can bind to hemoglobin in red blood cells, forming carboxyhemoglobin. This binding has a higher affinity than oxygen, reducing the blood's ability to transport oxygen to body tissues. Here's an explanation of how carbon monoxide affects the body:

1. Hemoglobin Binding:

Hemoglobin is a protein in red blood cells responsible for transporting oxygen from the lungs to the rest of the body. When carbon monoxide is inhaled, it binds to hemoglobin, forming carboxyhemoglobin. This binding is much stronger than that of oxygen to hemoglobin.

2. Reduced Oxygen Transport:

The formation of carboxyhemoglobin reduces the blood's capacity to carry oxygen. As a result, less oxygen is delivered to body tissues, leading to a condition known as carbon monoxide poisoning or CO poisoning.

3. Symptoms of CO Poisoning:

Symptoms of carbon monoxide poisoning include headache, dizziness, weakness, nausea, vomiting, confusion, and in severe cases, loss of consciousness and death. The severity of symptoms depends on the concentration of carbon monoxide in the air and the duration of exposure.

4. Sources of CO:

Carbon monoxide is produced by the incomplete combustion of carbon-containing fuels such as wood, gasoline, natural gas, and oil. Common sources include faulty heating systems, vehicle exhaust, gas appliances, and indoor burning of fuels without proper ventilation.

5. Prevention:

Preventing carbon monoxide exposure involves proper ventilation of indoor spaces, regular maintenance of heating systems and appliances, and using carbon monoxide detectors in homes and buildings. It is crucial to identify and address sources of CO to prevent poisoning.

6. Medical Treatment:

Treatment for carbon monoxide poisoning involves removing the individual from the source of exposure, providing oxygen therapy to facilitate the removal of CO from the body, and, in severe cases, administering hyperbaric oxygen therapy.

Due to its toxicity and the potential for serious health consequences, carbon monoxide exposure is a significant concern. Awareness of sources, proper preventive measures, and prompt medical intervention in cases of exposure are essential for minimizing the risks associated with this harmful gas.