Question

Distinguish between
(a) IRV and ERV
(b) inspiratory capacity and Expiratory capacity.
(c) Vital capacity and Total lung capacity.​

Answer 1

Answer:

1. Inspiratory reserve volume (IRV) is the maximum volume of air that can be inhaled after a normal inspiration and it is about 2500 – 3500 mL in the human lungs. Expiratory reserve volume (ERV) is the maximum volume of air that can be exhaled after a normal expiration and it is about 1000 – 1500 mL in the human lungs.

2. The vital capacity (VC) measures the maximum amount of air that can be inhaled or exhaled during a respiratory cycle. It is the sum of the expiratory reserve volume, tidal volume, and inspiratory reserve volume. The inspiratory capacity (IC) is the amount of air that can be inhaled after the end of a normal expiration.

3. The vital capacity (VC) measures the maximum amount of air that can be inhaled or exhaled during a respiratory cycle. ... The total lung capacity (TLC) is a measurement of the total amount of air that the lung can hold.

Answer 2

(a)

Inspiratory reserve volume (IRV)

1. It is the maximum volume of air that can be inhaled after a normal inspiration. 
2. It is about 2500 – 3500 mL in the human lungs.

Expiratory reserve volume (ERV)  

1. It is the maximum volume of air that can be exhaled after a normal expiration.
2. It is about 1000 – 1100 mL in the human lungs.

(b)

 Inspiratory capacity

1.  It is the volume of air that can be inhaled after a normal expiration. 
2. It includes tidal volume and inspiratory reserve volume.
3. IC = TV +IRV

Expiratory capacity (EC)  

1. It is the volume of air that can be exhaled after a normal inspiration.
2. It includes tidal volume and expiratory reserve volume. 
3. EC = TV + ERV

(c)

 Vital capacity (VC).

1. It is the maximum volume of air that can be exhaled after a maximum inspiration. It includes IC and ERV.  
2. It is about 4000 mL in the human lungs. 

Total lung capacity (TLC) 

1. It is the volume of air in the lungs after maximum inspiration.
2. It is about 5000 – 6000 mL in the human lungs.