Question

Jessa is a medical research assistant. She is examining antibodies under a microscope. She has to categorize each type of antibody based on their functions. Which type of antibody is responsible for each of the following functions?

IgE
a) Prevents bacteria and viruses from entering the body
b) Is responsible for identifying antigens and producing antibodies to fight the foreign substance
c) Is the front line of defense when fighting bacteria or viral antigens
d) Releases histamine during an allergic reaction

IgA
a) Prevents bacteria and viruses from entering the body
b) Is responsible for identifying antigens and producing antibodies to fight the foreign substance
c) Is the front line of defense when fighting bacteria or viral antigens
d) Releases histamine during an allergic reaction

IgM
a) Prevents bacteria and viruses from entering the body
b) Is responsible for identifying antigens and producing antibodies to fight the foreign substance
c) Is the front line of defense when fighting bacteria or viral antigens
d) Releases histamine during an allergic reaction

IgD
a) Prevents bacteria and viruses from entering the body
b) Is responsible for identifying antigens and producing antibodies to fight the foreign substance
c) Is the front line of defense when fighting bacteria or viral antigens
d) Releases histamine during an allergic reaction

Answer 1

IgE releases histamine during allergic reactions, IgA prevents pathogen entry at mucosal surfaces, IgM acts as the primary defense against pathogens in the blood, and IgD is involved in antigen recognition and B cell activation.

Step-by-step explanation:

Functions of Antibody Types IgE, IgA, IgM, and IgD

Jessa, a medical research assistant, is categorizing antibodies based on their functions. Let's clarify the specific roles of each antibody type:

• IgE is responsible for d) releasing histamine during an allergic reaction. It binds to mast cells and basophils and, upon interaction with an allergen, leads to degranulation and release of histamine, contributing to allergy symptoms.
• IgA, particularly its dimer form, is found in mucous membranes and secretions. It is responsible for a) preventing bacteria and viruses from entering the body, primarily by neutralizing pathogens in areas such as the respiratory and digestive tracts.
• IgM is the first antibody type to be produced in response to an antigen and is present as a monomer on the surface of B cells or as a pentamer in the blood. It is responsible for c) being the front line of defense when fighting bacteria or viral antigens, including activating the complement system for pathogen destruction.
• IgD is predominantly found as a receptor on naive B cells, with its primary known function being b) responsible for identifying antigens and producing antibodies to fight the foreign substance. This role in B cell activation is critical for the adaptive immune response.

Each class of antibodies plays a vital role in the immune response, providing a great variety of antibody functions critical to many adaptive immune responses.