The ciliary escalator allows unwanted particles to be swept __________.

Question

Quizplus · Accepted Answer

The ciliary escalator is a mechanism in the respiratory system that is responsible for sweeping unwanted particles, such as dust and mucus, upward towards the throat. From there, they are usually swallowed and expelled from the body. Therefore, the best choice is D, which states that unwanted particles are swept upward to the throat, where they are usually swallowed. The other choices are incorrect, as particles are not supposed to be swept downward into the lungs (A), into the bloodstream (B), or away when the smoker exhales (C).

The Ciliary Escalator Allows Unwanted Particles to Be Swept __________