key term - Mucociliary escalator

Definition

The mucociliary escalator is a defense mechanism in the respiratory tract where mucus traps inhaled particles and cilia move them upwards towards the throat to be expelled or swallowed. This process helps keep the respiratory tract clear of pathogens and debris.

5 Must Know Facts For Your Next Test

1. The mucociliary escalator consists of mucus-producing goblet cells and ciliated epithelial cells.
2. It is a critical component of innate nonspecific host defenses against respiratory infections.
3. Cilia beat rhythmically to move the mucus layer upwards from the lower respiratory tract to the pharynx.
4. Impairment of the mucociliary escalator can lead to increased susceptibility to respiratory infections, such as bronchitis and pneumonia.
5. Smoking, pollution, and certain genetic conditions like cystic fibrosis can damage or impair the function of the mucociliary escalator.

Review Questions

Related terms

Goblet Cells:

Specialized cells in the respiratory tract that produce mucus.

Cilia:

Hair-like structures on epithelial cells that move rhythmically to transport mucus.

Cystic Fibrosis:

A genetic disorder that affects mucus production and leads to impaired mucociliary clearance.