Why is it harder to breathe if surfactant is absent in the lungs?
Because the surfactant is a substance which decreases the surface tension in your lungs…that is it makes the expansion of your alveoli (part of your lungs) easier….so if it is absent, much friction will be encountered thus making your breathing difficult, and eventally may lead to alveolar collapse (medically known as atelectasis)
Without surfactant, your lungs would collapse. If you think of the alveoli (air sacks) in your lungs as balloons, if the opening is stuck together because it is dried out, air cant get in. It is the same for your lungs, if the air sacks are not 'coated' with surfactant (lubricant), air will not easily get in, making it difficult to breath. It can be a serious problem for premature babies, as they may not have enough surfactant, this can be helped by an injection from the doc.