What is the main function of respiratory system in a animal. supportingb bones-taiking oxygen into body-digesting food-pumping blood through body?

The main function of the respiratory system in an animal is to take oxygen into the body and expel carbon dioxide. Oxygen is a vital gas that is needed by all cells in the body to produce energy. Carbon dioxide is a waste product that is produced when cells use oxygen. The respiratory system works by bringing air into the lungs, where oxygen is absorbed into the bloodstream. The bloodstream then carries oxygen to all cells in the body. At the same time, carbon dioxide is released from the blood into the lungs and is expelled from the body when we breathe out.