Respiratory system Physiology-Multiple choice Questions (MCQ) - Lung Mechanics

Please Mark True or False

01.  Increased respiratory minute volume occurs with

a. Arterial pO2 of 100mmHg

b. Rise in body temperature

c. Brain damage

d. Renal tubular acidosis

e. Lowered barometric pressure


02. Increased in respiratory minute volume at rest occurs with

a. Acute rise in arterial pCO2

b. Arterial pO2 of 65 mmHg

c. Haemoglobin of 5g/dl

d. Breathing air containing 5% CO2

e. Rise in arterial blood pressure


03. Airway resistance to air flow

a. Varies directly with the velocity of flow

b. Varies directly with the fourth power of the radius

c. Is reduced when breathing helium – oxygen gas mixture

d. Is decreased at high altitude

e. Is increased in asthma


04. During quite respiration

a. Intra- pleural pressure is always sub atmospheric

b. Intra-alveolar pressure is always sub atmospheric

c. Volume of air left in the lungs at the end of expiration constitutes the residual volume

d. Volume of air left in the lungs at the end of inspiration constitutes the vital capacity

e. External intercostal muscles contract in the inspiratory phase


05. During maximal inspiration in a healthy adult

a. Intra pleural pressure rises to about 2 mm Hg

b. Venous return decreased

c. Skeletal muscles of the diaphragm relaxes

d. Alveolar ventilation increases

e. Heart rate is reduced


06. During inspiration there is an increase in

a. Intra-abdominal pressure

b. Intra- pulmonary

c. Intra- pleural pressure

d. Intra- oesophageal pressure

e. Intra thoracic pressure


07. Regarding pressure changes during respiration

a. Intra- pleural pressure is nearly equal to intra oesophageal pressure

b. During quite inspiration in an adult intra pleural pressure is about 6 mm Hg

c. During quite expiration the intra pleural pressure is slightly below atmospheric pressure

d. During quite expiration the intra pulmonary pressure is slightly above atmospheric pressure

e. Intra pleural pressure rises above atmospheric pressure with a forced expiration


08. Intra- pleural pressure

a. Is subatmospheric throughout normal inspiration and expiration

b. Becomes more subatmospheric with inspiration

c. Can be assessed by measuring intra gastric pressure

d. Become less subatmospheric during inspiration with a high air way resistane.

e. Rises above atmospheric pressure with a forced expiration against resistance.

Please visit following link for the Answers