<prompt> Concerning normal expiration during resting conditions:Expiration is generated by the expiratory musclesAlveolar pressure is less than atmospheric pressureIntrapleural pressure gradually falls becomes more negative during the expirationFlow velocity of the gas in cmsec in the large airways exceeds that in the terminal bronchioles  <response>: The velocity of the gas in the large airways exceeds that in the terminal bronchioles because the latter have a very large combined cross-sectional area. The other choices are incorrect: Under resting conditions, expiration is passive it is associated with an alveolar pressure that exceeds atmospheric pressure intrapleural pressure gradually increases becomes less negative during expiration and the diaphragm moves up as expiration proceeds. 