Question

What are MASP-1/2?

a) Mannose
b) Microbial
c) Monomeric antigen
d) Membrane

Answer 1

MASP-1/2 refers to Mannan-binding lectin-associated serine proteases involved in the lectin pathway of the complement system. Therefore, the correct answer is Mannose.Thus the correct option A.

Step-by-step explanation:

MASP-1/2, or Mannan-binding lectin-associated serine proteases 1 and 2, are key components of the lectin pathway within the human complement system. This system is a crucial part of the immune response, providing defense against pathogens. MASP-1 and MASP-2 are serine proteases that play a significant role in activating the lectin pathway by binding to mannose-binding lectin (MBL) or ficolins, which recognize microbial carbohydrates, especially those present on the surface of pathogens.

In more detail, MASP-1 and MASP-2 bind to MBL or ficolins when these molecules recognize and bind to microbial surfaces. This interaction triggers a cascade of events leading to the activation of the complement system, ultimately resulting in the elimination of the pathogen. The lectin pathway, including MASP-1/2, acts as a critical immune surveillance mechanism, contributing to the body's ability to identify and respond to foreign invaders.

Understanding the roles of MASP-1/2 in the lectin pathway is essential for comprehending the immune response and how the complement system functions in defense against infections. Therefore, the correct association with MASP-1/2 is the recognition of mannose, highlighting the importance of mannose-binding lectin in initiating the lectin pathway and the subsequent immune response.

Answer 2

MASP-1/2 are not directly related to MHC molecules or antigen presentation. However, MHC I is present on all nucleated cells and MHC II on certain immune cells. Antigens can be proteins or carbohydrates, and the complement system can be activated by antibodies on pathogens.

Step-by-step explanation:

MASP-1/2 refers to mannan-binding lectin serine protease 1 and 2, which are not directly related to what's typically referred to in Biology textbooks regarding antigen-presenting molecules. However, the question seems to touch on the topic of antigen presentation and the role of different MHC (Major Histocompatibility Complex) molecules in this process.

The MHC I molecules are found on nearly all nucleated cells and present endogenous antigens to CD8+ cytotoxic T cells. Conversely, MHC II molecules are only present on professional antigen-presenting cells like macrophages, dendritic cells, and B cells and present exogenous antigens to CD4+ helper T cells.

Antigens themselves can be composed of various substances such as carbohydrates or proteins. Complement activation is another immune mechanism where antibodies attached to pathogens activate the complement system, which can subsequently lead to the destruction of the pathogen.