Question

''Breathing cycle is rhythmic where as exchange of gas is a continuous process''? Justify this statement

Answer 1

Breathing cycle is rhythmic because it is a regular process of inspiration and expiration  in an oscillating cycle. Neuronal impulses are responsible for this control which transmits between the respiratory centers in the brain and the muscles involved in inspiration in the chest and diaphragm.

Gaseous exchange is a continuous process because it involves the process of diffusion. Diffusion of gas takes place from the region of high concentration to a region of low concentration which normally involves exchange of oxygen and carbon dioxide during the process of respiration in living organism and its environment. 

Answer 2

Answer:

The breathing cycle involves inhalation and exhalation of air due to alternate expansion and contraction of the thorasic cavity, thus it is a rythemic activity. But the exchange of gas is a continuous process as it takes place in between the blood and each and every cell, by diffusion.