Question

Name the process of inhalation and exhalation of air.

Answer 1

It is the process of movement of air inside and outside of the lungs which can be named as inhalation and exhalation, respectively. Various respiratory organs are involved in this process and it is carried out in a continuous manner throughout the life of an organism.

Complete answer:
The process of inhalation and exhalation of air is known as breathing. Inhalation and exhalation refers to bringing in oxygen and getting rid of carbon dioxide respectively. The process occurs with the help of diaphragm (large dome-shaped muscle) which is located beneath the lungs.

-Inhalation
It is also known as Inspiration. On breathing in air, contraction of diaphragm takes place and it is pulled downward. This leads to the expansion of the chest cavity which creates a partial vacuum that causes a rush of air into the lungs thereby filling up the expanded alveoli. This process involves taking in of oxygen rich air.

-Exhalation
It is also known as Expiration. It occurs after the gaseous exchange takes place in lungs. This process involves expulsion of air. In contrast to inhalation, during this process, muscles of diaphragm are relaxed and pushed upwards. This decreases chest cavity volume and increases the lung pressure thereby pushing out air present in lungs. During this process, carbon dioxide rich air is given out.

Note: A person normally breathes several times a day. One inhalation and one exhalation form one breath. Breathing rate refers to the number of times a person breathes per minute. In adults, breathing rate is normally 15-18 times per minute. But in case of heavy exercise, this rate often increases to 25 times per minute.