respiratory part 2 Flashcards
what is surface tension
force acting to pull liquids surface molecules together
what is the role of surfactants
surfactants reduce surface tension and less work os needed to expand the alveoli
reduce the tendency of alveolar walls to stick
what is long compliance
how easily the lungs stretch during inhalation
surface tension decreases compliance therefor surfactants increase
what is lung elasticity
the ability of the lung to return to its resting volume after stretched
what effect does low elasticity have
lungs are not able to return to resting volume once respiratory muscles relax, and therefor must actively expire
what is fibrotic lung disease
scarring of lung tissue
reduces compliance, makes inspiration difficult
must breath rapidly and shallow
what is emphysema
damage to elastic fibers, lung is less elastic
collapses more often
easily inflated but needs more energy to expire
what is asthma
inflammatory disease of respiratory airways
causes constriction of airways
how does diameter affect resistance
as diameter decrease, resistance increases
as diameter increases, resistance decreases
how is resistance related to pressure gradient
higher resistance needs a larger pressure gradient
lower resistance needs a smaller pressure gradient
how do parasympathetic nerve affects respiration
parasympathetic nerves stimulate bronchoconstriction
how do sympathetic nerves affect respiration
sympathetic nerves stimulate bronchodilaton
spirometer
measures lung capacity and volume
dead space (Vd)
air that doesn’t participate in gas exchange
- anatomical
- alveolar
tidal volume (Vt)
volume of air moved in one ventilatory cycle
