Match List I with List II. [2024]
| List I | List II | ||
| A. | Expiratory capacity | I. | Expiratory reserve volume + Tidal volume + Inspiratory reserve volume |
| B. | Functional residual capacity | II. | Tidal volume + Expiratory reserve volume |
| C. | Vital capacity | III. | Tidal volume + Inspiratory reserve volume |
| D. | Inspiratory capacity | IV. | Expiratory reserve volume + Residual volume |
Choose the correct answer from the options given below:
A-II, B-IV, C-I, D-III
A-III, B-II, C-IV, D-I
A-II, B-I, C-IV, D-III
A-I, B-III, C-II, D-IV
(1)
Expiratory Capacity (EC) is the total volume of air a person can expire after a normal inspiration. This includes tidal volume and expiratory reserve volume (TV + ERV).
Functional Residual Capacity (FRC) is the volume of air that will remain in the lungs after a normal expiration. This includes ERV + RV (residual volume).
Vital Capacity (VC) is the maximum volume of air a person can breathe in after a forced expiration. This includes ERV, TV and IRV.
Inspiratory Capacity (IC) is the total volume of air a person can inspire after a normal expiration. This includes tidal volume and inspiratory reserve volume (TV + IRV).
Vital capacity of lung is ________. [2023]
IRV + ERV + TV − RV
IRV + ERV + TV
IRV + ERV
IRV + ERV + TV + RV
(2)
Vital capacity (VC) is the maximum volume of air a person can breathe in after forced expiration or maximum volume of air a person can breathe out after forced inspiration. This includes ERV, TV and IRV.
Select the correct events that occur during inspiration. [2020]
(1) Contraction of diaphragm
(2) Contraction of external inter-costal muscles
(3) Pulmonary volume decreases
(4) Intra pulmonary pressure increases
(1) and (2)
(3) and (4)
(1), (2) and (4)
only (4)
(1)
Inspiration is initiated by the contraction of diaphragm that increases the volume of thoracic chamber in the antero-posterior axis. The contraction of external intercostal muscles lifts up the ribs and the sternum causing an increase in the volume of the thoracic chamber in the dorso-ventral axis. The overall increase in the thoracic volume causes a similar increase in pulmonary volume. An increase in pulmonary volume decreases the intra-pulmonary pressure to less than the atmospheric pressure which forces the air from outside to move into the lungs.
Tidal volume and expiratory reserve volume of an athlete is 500 mL and 1000 mL respectively. What will be his expiratory capacity if the residual volume is 1200 mL? [2019]
2700 mL
1500 mL
1700 mL
2200 mL
(2)
Expiratory capacity is the total volume of air a person can expire after normal inspiration. It includes tidal volume (TV) and expiratory reserve volume (ERV).
EC = TV + ERV = 500 mL + 1000 mL = 1500 mL
Select the correct statement. [2019]
Expiration occurs due to external intercostal muscles.
Intrapulmonary pressure is lower than the atmospheric pressure during inspiration.
Inspiration occurs when atmospheric pressure is less than intrapulmonary pressure.
Expiration is initiated due to contraction of diaphragm.
Match the items given in column I with those in column II and select the correct option given below. [2018]
| Column I | Column II | ||
| (A) | Tidal volume | (i) | 2500 – 3000 mL |
| (B) | Inspiratory reserve volume | (ii) | 1100 – 1200 mL |
| (C) | Expiratory reserve volume | (iii) | 500 – 550 mL |
| (D) | Residual volume | (iv) | 1000 – 1100 mL |
(A)-(iii), (B)-(ii), (C)-(i), (D)-(iv)
(A)-(iii), (B)-(i), (C)-(iv), (D)-(ii)
(A)-(i), (B)-(iv), (C)-(ii), (D)-(iii)
(A)-(iv), (B)-(iii), (C)-(ii), (D)-(i)
Lungs are made up of air-filled sacs, the alveoli. They do not collapse even after forceful expiration, because of [2017]
inspiratory reserve volume
tidal volume
expiratory reserve volume
residual volume
(4)
Residual volume is the volume of air which remains in the lungs after the most forceful expiration. This residual air enables the lungs to continue exchange of gases even after maximum exhalation. Due to this, lungs do not collapse even after forceful expiration.
Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because [2016]
there is a negative pressure in the lungs
there is a negative intrapleural pressure pulling at the lung walls
there is a positive intrapleural pressure
pressure in the lungs is higher than the atmospheric pressure.
(2)
Intrapleural pressure is the pressure of air within the pleural cavity. Intrapleural pressure is always negative, which acts like a suction to keep the lungs inflated and prevent them from collapsing. The negative intrapleural pressure is due to three main factors: surface tension of the alveolar fluid; elasticity of lungs; elasticity of thoracic wall. Normally, there is a difference between intrapleural and intrapulmonary pressure, which is called transpulmonary pressure. This transpulmonary pressure creates the suction to keep the lungs inflated. If there is no pressure difference, there is no suction and lungs will collapse.
