Question

A person suffers punctures in his chest cavity in an accident, without any damage to the lungs, its effect could be __________
A. Reduce breathing rate
B. Rapid increase in breathing rate
C. No change in respiration
D. Cessation of breathing

Answer 1

Hint: Cells utilizes oxygen for metabolism and produce energy along with substances like carbon dioxide which is harmful. It can wholly be achieved through the process of breathing. We all know that if our chest cavity is affected by some external issues, it will definitely affect our breathing process.

Complete answer:
We all are familiar with that oxygen is utilised by organisms to indirectly break down nutrient molecules such as glucose for energy to perform various activities of a normal lifestyle. Carbon dioxide which is harmful is also released during the various catabolic reaction. The process of exchange of oxygen from the atmosphere with carbon dioxide produced by the cells is called breaking, commonly known as respiration.

We know that the process of breathing takes place in two stages: inspiration during which atmospheric air is drawn in and expiration by which the alveolar air is released out. The pressure gradient that is present between the lungs and the atmosphere is responsible for the movement of air into and out of the lungs. Inspiration can only take place if the pressure that is inside the lungs is less as compared to atmospheric pressure or we can say that there is a negative pressure in the lungs as compared with respect to atmospheric pressure. Similarly, expiration takes place when the intra- pulmonary pressure is higher than the atmospheric pressure.

As the known movement of the air in and out of the lungs can is carried by the pressure gradient. Due to the puncturing of the chest cavity, the pressure inside the lungs is less as compared to the atmospheric pressure thus it will create negative pressure in the lungs with respect to the atmospheric atmosphere. The puncture in the chest affects this pressure gradient that is generally maintained by the lungs and thus may cause cessation of breathing.

Therefore the correct answer is option ‘D’.

Note: A healthy human breathes 12 - 16 times per minute on average. We can estimate the volume of air that is involved in the breathing movement by using up a spirometer. This equipment helps in the clinical assessment of pulmonary function.