Biology
Human Immunity and Blood
2,051 Questions
Human immunity and blood questions cover the physiological mechanisms protecting the body against diseases and the components of blood. Topics include blood groups, cell mediated immunity, monoclonal antibodies, and blood coagulation. These biology topics frequently appear in general science sections of competitive exams.
Blood groupsCell mediated immunityMonoclonal antibodiesBlood coagulationCancer immunology
Human Immunity and Blood Questions
Which type of immunological disorder is characterized by an exaggerated immune response to harmless substances, such as pollen or dust?
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Immunodeficiency disorder
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Allergic disorder
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Autoimmune disorder
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Hypersensitivity disorder
B
Correct answer
Explanation
Allergic disorders, such as hay fever and asthma, are caused by an exaggerated immune response to harmless substances, leading to symptoms like sneezing, runny nose, and difficulty breathing.
What is the most common type of immunodeficiency disorder?
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Severe combined immunodeficiency (SCID)
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Common variable immunodeficiency (CVID)
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X-linked agammaglobulinemia (XLA)
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DiGeorge syndrome
B
Correct answer
Explanation
Common variable immunodeficiency (CVID) is the most common type of immunodeficiency disorder, characterized by low levels of antibodies and an increased susceptibility to infections.
Which type of immunological disorder is characterized by an overactive immune response, leading to inflammation and tissue damage?
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Immunodeficiency disorder
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Allergic disorder
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Autoimmune disorder
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Hypersensitivity disorder
D
Correct answer
Explanation
Hypersensitivity disorders, also known as immune-mediated disorders, are characterized by an overactive immune response, leading to inflammation and tissue damage.
What is the most common type of hypersensitivity disorder?
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Type I hypersensitivity (immediate hypersensitivity)
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Type II hypersensitivity (cytotoxic hypersensitivity)
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Type III hypersensitivity (immune complex hypersensitivity)
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Type IV hypersensitivity (delayed-type hypersensitivity)
A
Correct answer
Explanation
Type I hypersensitivity, also known as immediate hypersensitivity, is the most common type of hypersensitivity disorder, characterized by a rapid immune response to allergens, leading to symptoms such as sneezing, runny nose, and difficulty breathing.
What discovery enabled the development of modern vaccines?
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Immunology
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Pathology
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Epidemiology
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Virology
A
Correct answer
Explanation
Immunology, the study of the immune system, led to the understanding of how vaccines work and the development of effective vaccines against various diseases.
Where do B cells mature and differentiate into plasma cells?
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Bone marrow
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Thymus
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Spleen
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Lymph nodes
A
Correct answer
Explanation
B cells mature and differentiate into plasma cells primarily in the bone marrow, where they undergo a process called B cell development.
What is the role of B cells in humoral immunity?
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Producing antibodies
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
B cells play a central role in humoral immunity by producing antibodies that specifically bind to and neutralize antigens, marking them for destruction by other immune cells.
What is the process by which B cells become activated and differentiate into plasma cells?
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Clonal selection
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Apoptosis
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Cytokine signaling
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Phagocytosis
A
Correct answer
Explanation
B cells become activated through a process called clonal selection, where specific antigens bind to B cell receptors, triggering proliferation and differentiation into plasma cells, which produce large quantities of antibodies.
What is the difference between IgM and IgG antibodies?
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IgM is a monomer, while IgG is a dimer
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IgM is produced during the primary immune response, while IgG is produced during the secondary immune response
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IgM is found in saliva and tears, while IgG is found in blood and cerebrospinal fluid
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All of the above
D
Correct answer
Explanation
IgM is a monomeric antibody produced during the primary immune response, found in saliva and tears. IgG is a dimeric antibody produced during the secondary immune response, found in blood and cerebrospinal fluid.
What is the role of B cells in autoimmune diseases?
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Producing antibodies against self-antigens
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
In autoimmune diseases, B cells malfunction and produce antibodies against the body's own tissues, leading to inflammation and tissue damage.
What is the role of B cells in cancer immunotherapy?
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Producing antibodies against cancer cells
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
B cells can be engineered to produce antibodies that specifically target and destroy cancer cells, a promising approach in cancer immunotherapy.
What are some common B cell disorders?
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Multiple myeloma
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Chronic lymphocytic leukemia
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Hodgkin lymphoma
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All of the above
D
Correct answer
Explanation
Multiple myeloma, chronic lymphocytic leukemia, and Hodgkin lymphoma are examples of common B cell disorders that affect B cell development, function, or proliferation.
What is the role of B cells in the development of allergies?
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Producing antibodies against allergens
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
In allergies, B cells produce antibodies against harmless substances (allergens), leading to an exaggerated immune response and symptoms such as sneezing, runny nose, and watery eyes.
What is the role of B cells in the prevention of infections?
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Producing antibodies against pathogens
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
B cells play a critical role in preventing infections by producing antibodies that neutralize pathogens, preventing their entry into cells and causing disease.
What is the role of B cells in the maintenance of immune memory?
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Producing antibodies against pathogens
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Killing infected cells
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Releasing cytokines
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Activating macrophages
A
Correct answer
Explanation
B cells contribute to immune memory by producing memory B cells, which remain in the body after an infection and can rapidly produce antibodies upon re-exposure to the same pathogen, providing long-term protection.