The respiratory system is necessary for an organism's body to live because it introduces oxygen-rich air, which is needed to perform vital functions, while at the same time promoting the elimination of carbon dioxide.

Explanation:

Oxygen (O₂) is necessary for life because it participates in the process of cellular respiration, a mechanism that allows the oxidation of glucose to form energy in the form of ATP.

The respiratory system is made up of a set of organs that carry air into the body and facilitate gas exchange, i.e. the entry of O₂ into the blood and the elimination of potentially harmful carbon dioxide (CO₂).

This exchange of gases occurs in structures called pulmonary alveoli, whose surface is located in relation to the pulmonary capillary vessels.

The entry of air into the lungs brings O₂ to the alveoli, which will diffuse into the pulmonary capillary for the process of hematosis or oxygenation of the blood.
CO₂, a product of metabolism, leaves the capillary to the alveoli, to join the air that will be expelled during expiration.

Both O₂ and CO₂ require a transport molecule in the blood, red blood cell hemoglobin, which binds the gases and allows them to be transported to and from the tissues.

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Exchange of respiratory gases brainly.com/question/4569375