Question

Lysozyme that is present in perspiration, saliva and tears, destroys

• A. All viruses
• B. Certain types of bacteria
• C. Most virus infected cells
• D. Certain fungi

Answer 1

The Correct Option is B

Lysozyme is an enzyme that is commonly found in body fluids such as perspiration, saliva, and tears. It plays a crucial role in the body's innate immune system by providing a first line of defense against bacterial infection. Let's explore the role of lysozyme and why the correct answer is "Certain types of bacteria."

1. Understanding Lysozyme:

   Lysozyme is an antimicrobial enzyme produced by animals that forms part of the innate immune system. It has the ability to break down the peptidoglycan walls of bacteria. This action disrupts the structural integrity of the bacterial cell wall, leading to cell lysis and death.

2. Specific Action on Bacteria:

   The peptidoglycan layer is a crucial component of the bacterial cell wall, especially in Gram-positive bacteria. By cleaving the bonds in this layer, lysozyme effectively destroys these types of bacteria.

3. Ruling Out Other Options:
   • All viruses: Lysozyme is not effective against viruses because viruses do not have peptidoglycan cell walls.
   • Most virus infected cells: Lysozyme does not target virus-infected host cells as it specifically acts on bacterial cell walls.
   • Certain fungi: Fungi have a different type of cell wall structure, which does not contain the same peptidoglycan targeted by lysozyme.
4. Conclusion:

   Based on its mode of action, lysozyme is effective against certain types of bacteria. This makes the correct answer "Certain types of bacteria."

In summary, lysozyme provides an important defense mechanism by targeting and destroying bacteria, particularly those with peptidoglycan-rich cell walls, thus contributing to the protection of body surfaces that are exposed to potential infections.