BIOC34H3 Chapter Notes -Intrapleural Pressure, Electronvolt, Surface Tension
Document Summary
It is the volume that can be exhaled after tv (1 mark). Activity 2: examining the effect of changing airway resistance on respiratory volumes: there is a decrease in fev1 due to increased resistance with a decreasing airway radius (1 mark). Premature infancies have little or no surfactant (0. 5 marks). This leads to alveolar collapse or low compliance. Therefore there needs to be an increased effort to breathe or a decrease in surface tension (1 mark) Activity 4: investigating intrapleural pressure: explain your reasoning. Intrapleural pressure = atmospheric pressure (2 marks): lung does not re-inflate because intrapleural pressure is no longer negative. The lung cannot overcome the increase in ipp due to air in the pleural cavity. (1 marks) Activity 5: exploring various breathing patterns: pco2 during rapid breathing falls (0. 5 marks) due to more co2 being exhaled (0. 5 marks) faster than it can be replaced in the body (blood) by metabolism (0. 5 marks).
