Chapter 21, Problem 1SA

Summary Introduction

To review:

The cause of upper respiratory infection through eye contamination.

Introduction:

The respiratory system of the humans is one of the prime biological system wherein exchange of gases and breathing process is accomplished. The lungs are known to be the primary organ, which participates in this system. This system is segregated into upper and lower respiratory system.

Explanation of Solution

The upper respiratory system involves the nose, the nasal passage, trachea, larynx, and pharynx. The nasal passage comprises cilia, which are finger-like projections that block the microorganisms to enter into the lungs. The infection usually is a common cold, which is caused by a virus. The symptoms involve the runny nose, sore throat, cough, congestion, and sneezing.

The microorganisms can enter the respiratory system either via nose, throat, or eye. From the nose, they can directly escape and enter the respiratory system; from the throat, they may enter via the mouth and enter the respiratory system; or from eyes, the organisms can enter the surface of the eye and enter the nasopharynx passage via the nasolacrimal duct. Therefore, eye contamination may lead to the infection in the upper region of the respiratory system.

Conclusion

Therefore, it can be concluded that the pathogens can enter from the surface of the eye and enter the respiratory system via the nasolacrimal duct.