Question

Which of the following is the most important muscular structure in respiratory system of human?

(a) External intercoastal muscle

(b) Internal intercoastal muscle

(c) Diaphgram

(d) Vertebral column

The question was posed to me during an interview for a job.

This interesting question is from Mechanism of Breathing-2 topic in chapter Breathing and Exchange of Gases of Biology – Class 11

Answer 1

Right answer is (c) Diaphgram

The explanation is: Diaphgram is the most important muscular structure in respiratory system of human. At the time of inspiration, diaphgram contracts leading to increase in thoracic volume whereas during expiration it relaxes causing decrease in thoracic volume.