Free CMT Immunology & Serology Questions and Answers

Question 1

Which immunoglobulin is primarily involved in allergic reactions?

Accepted Answer

IgE

Answer

Immunoglobulin E (IgE) is the primary antibody class responsible for mediating allergic reactions and responses to parasitic infections. When an allergen is encountered, IgE binds to mast cells and basophils, triggering the release of histamine and other inflammatory mediators. This cascade of events leads to the characteristic symptoms of allergies, such as hives, sneezing, or anaphylaxis.

Question 2

What is the first antibody produced in a primary immune response?

Accepted Answer

IgM

Answer

Immunoglobulin M (IgM) is the first antibody produced and secreted by plasma cells during a primary immune response to a new antigen. Its pentameric structure allows it to efficiently bind multiple antigens, making it highly effective at activating the complement system and agglutinating pathogens. While other antibodies like IgG appear later, IgM provides immediate, short-term protection.

Question 3

Which test is commonly used to detect antibodies to HIV?

Accepted Answer

ELISA

Answer

ELISA (Enzyme-Linked Immunosorbent Assay) is a widely used and highly sensitive screening test for detecting antibodies to HIV in a blood sample. It works by using an enzyme-linked antibody to detect the presence of specific antibodies or antigens, indicating exposure to the virus. While Western blot is a confirmatory test and PCR detects viral genetic material, ELISA is the standard initial screening method due to its cost-effectiveness and high throughput.

Question 4

What is the primary function of T-helper cells?

Accepted Answer

Activate B cells and immune cells

Answer

T-helper cells (CD4+ T cells) are crucial orchestrators of the adaptive immune response. They recognize antigens presented by antigen-presenting cells and then release cytokines that activate other immune cells, including B cells to produce antibodies, cytotoxic T cells to kill infected cells, and macrophages. This activation is essential for coordinating an effective and targeted immune response against pathogens.

Question 5

Which complement pathway is activated by antigen-antibody complexes?

Accepted Answer

Classical

Answer

The classical complement pathway is primarily activated by the binding of antibodies (specifically IgG or IgM) to antigens, forming antigen-antibody complexes. This binding initiates a cascade of protein interactions, leading to the formation of the membrane attack complex (MAC) and subsequent lysis of target cells. The alternative and lectin pathways are activated by different triggers.

CMT - Certified Medical Technologist Practice Test

CMT - Certified Medical Technologist Practice Test

Free CMT Immunology & Serology Questions and Answers