Question

What would happen if whole respiratory tree remains lined by PSCCGE-
a. Efficient removal of pathogen takes place
b. No exchange occurs in the bronchial tree in this case
c. No exchange is possible in respiratory tree
d. Respiration and breathing remains proper

Answer 1

Hint: The respiratory system is the means by which the process of respiration takes place in humans. The respiratory system is known to comprise the respiratory tract that is lined with respiratory epithelium cells.

Complete answer:
During respiration air from the atmosphere is breathed in through the nose following which it travels through a nasal passage that is covered by a layer of nasal mucosa and moves into the pharynx. From this the air moves to the larynx, the trachea, the bronchi, the bronchioles and finally to the alveoli where the exchange of gases actually takes place. The respiratory tract is known to be covered with PSCCGE or pseudostratified ciliated columnar epithelial cells commonly known as respiratory epithelial cells as well as glands and goblet cells that produce mucus. The cilia of the epithelial cells move in one direction that leads to the movement of the mucus and other airborne substances towards the throat. These epithelial cells along with the mucus help in efficient removal of pathogens by either their swallowing in the acidic stomach or removal by spitting. The beating of the cilia also prevents the accumulation of the mucus in the lungs.

Hence the correct answer is option (a).

Note: Though the respiratory systems have developed means to protect itself from pathogens but still respiratory infections are seen to develop such as flu, common cold, bronchitis, pneumonia, etc. as a result of the respiratory tree not being able to remove the pathogen. If not treated correctly they can give rise to severe health issues.