* not completed

. In a normal healthy individual with a total lung capacity of 6 litres:

The tidal volume at rest is about 1 litre. correct incorrect

The functional residual capacity would be about 2 litres. correct incorrect

The expiratory reserve volume at rest would be about 2 litres. correct incorrect

The FEV1 would be equivalent to about 4 litres. correct incorrect

* not completed

. The change in volume of the chest during inspiration is determined solely by the compliance of the lungs.

True correct incorrect

False correct incorrect

* not completed

. The change in the volume of the lungs with pressure is a measure of their compliance

True correct incorrect

False correct incorrect

* not completed

. The recoil of the lungs assists expiration

True correct incorrect

False correct incorrect

* not completed

. Pulmonary surfactant reduces the surface tension of the fluid lining the alveoli.

True correct incorrect

False correct incorrect

* not completed

. The intercostal muscles are the principal respiratory muscles.

True correct incorrect

False correct incorrect

* not completed

. Turbulent airflow in the upper airways accounts for about a third of the total airways resistance.

True correct incorrect

False correct incorrect

* not completed

. The lung volume at which the airways begin to collapse during a forced expiration is the residual volume.

True correct incorrect

False correct incorrect

* not completed

. In an estimate of functional residual capacity, a subject breathes an air- helium mixture from a spirometer. The spirometer has a volume of 10 l and the concentration of helium before the subject breathes the gas mixture is 5.0%. After the subject has breathed from the spirometer, the fractional concentration of helium has fallen to 4.17 %. What is the FRC? (Calculate your answer to two significant figures).

1.5 litres correct incorrect

2.5 litres correct incorrect

2.0 litres correct incorrect

1.8 litres correct incorrect