What would life be like without the respiratory system?

Answer 1

All of this breathing couldn't happen without the respiratory system, which includes the nose, throat, voice box, windpipe, and lungs.

At the top of the respiratory system, the nostrils (also called nares) act as the air intake, bringing air into the nose, where it's warmed and humidified. Tiny hairs called cilia protect the nasal passageways and other parts of the respiratory tract, filtering out dust and other particles that enter the nose through the breathed air.

Air can also be taken in through the mouth.

So the quick answer is that there would be no life.

So let me assume you mean if you breathed differently.

Even insects who breath differently have a respiratory system. Air enters the respiratory systems of most insects through a series of external openings called spiracles. These external openings, which act as muscular valves in some insects, lead to the internal respiratory system, a densely networked array of tubes called tracheae. This network of transverse and longitudinal tracheae equalizes pressure throughout the system.

The tracheae branch repeatedly, eventually forming tracheoles, which are blind-ended, water-filled compartments approximately one micrometer in diameter. It is at this level of the tracheoles that oxygen is delivered to the cells for respiration.

The tracheae are water-filled due to the permeable membrane of the surrounding tissues. During locomotion, the water level retracts due the increase in concentration of lactic acid in the muscle cells. This lowers the water potential and the water is drawn back into the cells via osmosis and air is brought closer to the muscle cells. The diffusion pathway is then reduced and gases can be transferred more easily.