Biology · Gaseous Exchange

Breathing is mechanical process consisting of two phases i.e.inspiration and expiration.

Breathing involves a rhythmic cycle, but it consists of only two primary phases: inspiration and expiration. Four phases would imply additional processes not involved in basic breathing.

Breathing cannot be comprised of just one phase as it involves both taking in oxygen (inspiration) and expelling carbon dioxide (expiration).

While there are processes involved in breathing, it fundamentally consists of two main phases: inspiration and expiration. A third phase would be inaccurate.

Correct! Breathing is a mechanical process that consists of two phases: inspiration, where air is drawn into the lungs, and expiration, where air is expelled.