Mechanism of Breathing
Mechanism of Breathing: Overview
This topic covers concepts, such as, Mechanism of Breathing,Intercostal Muscles,Spirometer etc.
Important Questions on Mechanism of Breathing
Listed below are four respiratory capacities (i-iv) and four jumbled respiratory volumes of a normal human adult:
Respiratory capacities | Respiratory volumes | ||
---|---|---|---|
(i) | Residual volume | (a) | 2500 mL |
(ii) | Vital capacity | (b) | 3500 mL |
(iii) | Inspiratory reserve volume | (c) | 1200 mL |
(iv) | Inspiratory capacity | (d) | 4500 mL |
Which one of the following pairs of capacities and volumes is matched correctly with each other?

Is pulmonary ventilation and breathing the same?

Read the following steps and arrange them in correct sequence for the process of inspiration:
A. Increase thoracic volume
B. Air moves into lungs
C. The contraction in diaphragm and EICM
D. Increase pulmonary volume
E. Lungs expand
F. Decrease the pulmonary pressure (IPP)

Assertion (A) : Expiration is a passive process.
Reason (R) : In this process, muscles of diaphragm and external intercostal muscles relax.
The correct option among the following is

Assertion: Inspiration is an active process.
Reason: It takes place by the contraction of muscles of diaphragm and external intercostal muscles.
The correct option among the following is

Which one of the following is a possibility for most of us in regard to breathing, by making conscious effort?

What is artificial ventilation?

Which of the following doesn’t occur during inspiration?

During inspiration, diaphragm_____ and_____ pressure develops in the lungs.

Mark the correct option from the following relationships between respiratory volumes and capacities.
(i) Vital Capacity (VC) = Tidal Volume (TV) + Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV).
(ii) Inspiratory Capacity (IC) = Tidal Volume + Residual Volume
(iii)Tidal Volume (TV) = Inspiratory Capacity (IC) - Inspiratory Reserve Volume (IRV)
(iv) Residual Volume (RV) = Vital Capacity (VC) - Inspiratory Reserve Volume (IRV)

Match the following.
Tidal volume | of air |
Inspiratory reserve volume |
of air |
Expiratory reserve volume |
of air |
Residual volume | of air |
Vital capacity | of air |

Match the following.
Tidal volume |
Tidal volume and inspiratory reserve volume and expiratory reserve volume. |
Inspiratory reserve volume | Additional volume of air a person can inspire by a forcible inspiration. |
Expiratory reserve volume |
Volume of air remaining in the lungs even after a forcible expiration. |
Residual volume | Tidal volume and inspiratory reserve volume. |
Inspiratory reserve capacity |
Volume of air inspired or expired during a normal respiration. |
Vital capacity | Vital capacity + Residual volume. |
Total lung capacity | Additional volume of air a person can expire by a forcible expiration. |

We can increase the strength of inspiration and expiration by the help of additional muscles in

On an average, a healthy human breathes how many times per minute?

The volume of air involved in breathing movements can be estimated by using a _____which helps in clinical assessment of pulmonary functions.

Functional residual capacity can be represented as

Inspiratory reserve volume + tidal volume + expiratory reserve volume is equivalent to:

Arrange the following events of respiration in proper sequence:
I. Breathing or pulmonary ventilation by which atmospheric air is drawn in and rich alveolar air is expelled out.
II. Diffusion of oxygen and carbon dioxide across the alveolar membrane.
III. Transport of gases by blood.
IV. Diffusion of oxygen and carbon dioxide across blood and tissue.
V. Utilisation of oxygen by the cells for metabolism and release of carbon dioxide.

In human body, rib-cage and sternum move upward and outward during

What are the two types of intercostal muscles?
