Important Immunology Multiple Choice Questions on Immune System and Antibodies
1) The branch of Biology, which involves the study of immune systems in all organisms is called_________.
(a) Zoology
(b) Microbiology
(c) Immunology
(d) Biotechnology
Sol: (c) Immunology.
2) Which of the following Immunity is obtained during a Lifetime?
(a) Acquired Immunity
(b) Active Immunity
(c) Passive Immunity
(d) None of the above
Sol: (a) Acquired Immunity.
3) How many types of Antibodies are there?
(a) Five
(b) Three
(c) Two
(d) Four
Sol: (a) Five.
4) Which of the following cells is involved in Cell-mediated Immunity?
(a) Leukaemia
(b) T cells
(c) Mast cells
(d) Thrombocytes
Sol: (b) T cells.
5) Which of the following protects our body against Disease-causing Pathogens?
(a) Respiratory System
(b) Immune System
(c) Digestive System
(d) Respiratory System
Sol: (b) Immune System.
6) Hepatitis is an example of _______.
(a) Subunit Vaccine
(b) Killer Vaccine
(c) Toxoids Vaccine
(d) Recombinant Vaccine
Sol: (d) Recombinant Vaccine.
7) Which of the following statements is true about the IgM of Humans?
(a) IgM can cross the placenta
(b) IgM can protect the mucosal surface
(c) IgM is produced by high-affinity plasma cells
(d) IgM is primarily restricted in the circulation
Sol:(d) IgM is primarily restricted in the circulation.
8) Which of the following statements is true about TNF alpha?
(a) Evoke Th cells
(b) Induce TGF beta production
(c) Decrease vascular permeability
(d) Increases the expression of adhesion molecules
Sol: (d) Increases the expression of adhesion molecules.
9) The cytotoxic T cells recognize Antigen in association with_________.
(a) Class III MHC determinants
(b) Class II MHC determinants
(c) Class I MHC determinants
(d) Both Class I and II MHC determinants
Sol: (d) Both Class I and II MHC determinants.
10) Which of the following Cytokines can increase the body temperature directly?
(a) Il-2
(b) IL-3
(c) IL-6
(d) IL-8
Sol: (c) IL-6.
11) Which of the following can inhibit Inflammation?
(a) RO
(b) TNFɑ
(c) Protein C
(d) Neuropeptide Y
Sol: (c) Protein C.
12) Which of the following statements is true about the Th-1 Cells?
(a) They do not express CD4
(b)They do not produce TNF𝞬
(c)They do not activate macrophages
(d) They do not bind to soluble proteins
Sol: (d) They do not bind to soluble proteins.
13) Which of the following statements is false about the receptors of Innate Immune System?
(a) They include MHC complexes
(b) They include scavenger receptors
(c) They recognize their molecular patterns
(d) They are included in the Toll family of receptors.
Sol:(a) They include MHC complexes.
14) The stimulation of antigen-specific T-cells by appropriately presented antigen, alone results in _________.
(a) Allergies
(b) Cytotoxicity
(c) Cell division
(d) Production of IL-3
Sol: (a) Allergies.
15) The Thymus independent type I antigen are _________.
(a) Viral nucleic acids
(b) Bacterial nucleic acids
(c) Small proteins of bacterial origin
(d) The polysaccharide of bacterial origin
Sol:(d) The polysaccharide of bacterial origin.
FAQs on Immunology MCQs with Answers for Exam Preparation
1. What are MCQs in immunology?
MCQs in immunology are multiple-choice questions designed to test knowledge of key concepts in immunology, the study of the immune system. These questions typically assess understanding of:
- Definitions of terms like antigen, antibody, and immunity
- Functions of B cells, T cells, and macrophages
- Mechanisms such as humoral immunity and cell-mediated immunity
- Clinical concepts like vaccination and hypersensitivity reactions
They are commonly used in biology exams, medical entrance tests, and competitive exams to evaluate conceptual clarity and application skills.
2. What is the difference between innate immunity and adaptive immunity?
The main difference between innate immunity and adaptive immunity is that innate immunity provides immediate, non-specific defense, while adaptive immunity is specific and develops memory. Key differences include:
- Innate immunity: Present from birth, rapid response, no immunological memory (e.g., skin barriers, phagocytes)
- Adaptive immunity: Develops after exposure, antigen-specific, forms memory cells (involves B lymphocytes and T lymphocytes)
This distinction is frequently tested in immunology MCQs and competitive biology exams.
3. What is an antigen in immunology?
An antigen is any substance that triggers an immune response by being recognized as foreign by the immune system. Antigens are usually:
- Proteins or polysaccharides on the surface of pathogens
- Recognized by B-cell receptors or T-cell receptors
- Capable of inducing production of specific antibodies
In MCQs on immunology, antigens are often contrasted with antibodies to test conceptual clarity.
4. What is the function of antibodies?
The primary function of antibodies is to specifically bind to antigens and help eliminate pathogens from the body. Also known as immunoglobulins (Ig), they perform several roles:
- Neutralization of toxins and viruses
- Opsonization to enhance phagocytosis
- Activation of the complement system
Antibody structure and function are frequently tested topics in immunology multiple-choice questions.
5. What are the different types of immunoglobulins?
The five main types of immunoglobulins are IgG, IgA, IgM, IgE, and IgD, each with distinct roles in immunity. They include:
- IgG: Most abundant; provides long-term protection and crosses the placenta
- IgA: Found in mucosal secretions like saliva and breast milk
- IgM: First antibody produced in primary immune response
- IgE: Involved in allergic reactions and defense against parasites
- IgD: Functions mainly as a receptor on B cells
Identification of immunoglobulin classes is a common MCQ topic in immunology.
6. What is cell-mediated immunity?
Cell-mediated immunity is an immune response that involves T lymphocytes rather than antibodies to eliminate infected or abnormal cells. It mainly includes:
- Cytotoxic T cells (CD8+) that destroy virus-infected or cancer cells
- Helper T cells (CD4+) that activate other immune cells
- Recognition of antigens presented by MHC molecules
This type of adaptive immunity is crucial against intracellular pathogens and is frequently tested in biology MCQs.
7. What is the complement system in immunology?
The complement system is a group of plasma proteins that enhance the ability of antibodies and phagocytic cells to clear pathogens. It functions through:
- Opsonization of microbes
- Formation of the membrane attack complex (MAC)
- Promotion of inflammation
Complement activation pathways—classical, alternative, and lectin—are commonly asked concepts in immunology multiple-choice questions.
8. What is the role of MHC in the immune response?
The Major Histocompatibility Complex (MHC) presents antigen fragments to T cells to initiate adaptive immune responses. Its key classes are:
- MHC Class I: Presents antigens to cytotoxic T cells (CD8+)
- MHC Class II: Presents antigens to helper T cells (CD4+)
Understanding MHC function and antigen presentation is essential for solving MCQs on immunology and transplantation biology.
9. What is active immunity and passive immunity?
Active immunity is protection developed by an individual's own immune system, while passive immunity is protection gained by transfer of ready-made antibodies. Differences include:
- Active immunity: Produced after infection or vaccination; long-lasting and forms memory cells
- Passive immunity: Acquired through maternal antibodies or antibody injections; immediate but short-lived
This comparison is a high-frequency question in immunology MCQs and entrance examinations.
10. What is a vaccine and how does it work?
A vaccine is a biological preparation that stimulates the immune system to develop protection against a specific pathogen without causing disease. It works by:
- Introducing weakened, inactivated, or antigenic components of a pathogen
- Activating B cells and T cells
- Forming long-lasting memory cells
Vaccination induces active immunity and is a central concept in immunology and public health MCQs.
