Which therapeutic gas is noted for its colorless, tasteless, and odorless characteristics and can support life?

Oxygen is a therapeutic gas that is essential for life, as it is required for cellular respiration in the human body. Its colorless, tasteless, and odorless characteristics make it a unique element that is naturally present in the atmosphere and crucial for sustaining life.

When oxygen is inhaled, it binds to hemoglobin in red blood cells, facilitating the transport of oxygen throughout the body. This is fundamental for the production of energy in cells. The properties of being colorless, tasteless, and odorless contribute to its safety in various medical applications, as it can be administered without causing discomfort or adverse sensory reactions in patients.

The other gases mentioned do not share these characteristics in relation to supporting life at the same level. For example, carbon dioxide is a waste product of respiration and can be harmful in excessive amounts. Helium, while safe to breathe in certain contexts, does not support life as it does not participate in biological processes. Nitric oxide, although important in specific therapeutic situations, is not a primary gas for supporting life in the same way that oxygen is. Hence, oxygen stands out as the gas noted for its life-sustaining properties and its essential role in respiration.