Biology
Human Immunity and Blood
2,096 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
What is the role of tissue typing in transplantation immunology?
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To determine the compatibility of donor and recipient tissues
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To identify potential risks of rejection
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To select the most suitable immunosuppressive regimen
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All of the above
D
Correct answer
Explanation
Tissue typing in transplantation immunology is used to determine the compatibility of donor and recipient tissues, identify potential risks of rejection, and select the most suitable immunosuppressive regimen.
What is the mechanism of action of adoptive cell therapy?
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Stimulating the production of antibodies
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Introducing tumor-specific antigens into the body
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Engineering immune cells to recognize and attack cancer cells
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Blocking the activity of immunosuppressive cells
C
Correct answer
Explanation
Adoptive cell therapy involves modifying and expanding a patient's own immune cells, such as T cells, to recognize and attack cancer cells more effectively.
What is the primary mechanism of action of immunotherapy in cancer treatment?
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Inhibiting cancer cell growth
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Stimulating the immune system to attack cancer cells
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Replacing damaged cells with healthy cells
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Blocking the blood supply to tumors
B
Correct answer
Explanation
Immunotherapy works by stimulating the patient's immune system to recognize and attack cancer cells.
Which type of white blood cell is responsible for phagocytosis?
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Neutrophils
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Lymphocytes
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Eosinophils
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Basophils
A
Correct answer
Explanation
Neutrophils are the most abundant type of phagocytes in the blood and are the primary cells responsible for phagocytosis during the early stages of an immune response.
What is the process by which phagocytes engulf and internalize foreign particles called?
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Chemotaxis
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Opsonization
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Phagocytosis
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Cytokinesis
C
Correct answer
Explanation
Phagocytosis is the process by which phagocytes extend their pseudopodia and engulf foreign particles, forming a phagosome.
What is the role of opsonins in phagocytosis?
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Activating complement proteins
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Binding to pathogens and enhancing phagocytosis
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Producing antibodies
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Releasing histamine
B
Correct answer
Explanation
Opsonins are proteins that coat pathogens, making them more recognizable and easier for phagocytes to engulf.
Which of the following is NOT a type of phagocyte?
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Neutrophils
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Macrophages
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Dendritic cells
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Erythrocytes
D
Correct answer
Explanation
Erythrocytes, also known as red blood cells, are not phagocytes. Phagocytes are specialized white blood cells that engulf and destroy pathogens.
Which of the following is a type of intracellular killing mechanism used by phagocytes?
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Antibody-mediated cytotoxicity
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Complement-mediated cytotoxicity
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Phagocytosis
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Oxidative burst
D
Correct answer
Explanation
Oxidative burst is an intracellular killing mechanism used by phagocytes to destroy engulfed pathogens. It involves the production of reactive oxygen species (ROS) and other antimicrobial substances that kill the pathogens.
What is the role of macrophages in phagocytosis?
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They are the primary phagocytes in the blood
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They are tissue-resident phagocytes
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They produce antibodies
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They release histamine
B
Correct answer
Explanation
Macrophages are tissue-resident phagocytes that are found in various tissues and organs throughout the body. They play a crucial role in phagocytosing pathogens, cellular debris, and foreign particles.
Which of the following is NOT a function of phagocytes?
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Engulfing and destroying pathogens
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Producing antibodies
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Presenting antigens to immune cells
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Releasing cytokines
B
Correct answer
Explanation
Phagocytes do not produce antibodies. Antibody production is a function of B cells and plasma cells.
What is the role of dendritic cells in phagocytosis?
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They are the primary phagocytes in the blood
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They are tissue-resident phagocytes
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They present antigens to immune cells
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They release histamine
C
Correct answer
Explanation
Dendritic cells are specialized phagocytes that are particularly adept at capturing and presenting antigens to immune cells, such as T cells. This process is crucial for initiating an adaptive immune response.
Which of the following is a type of phagocytic cell found in the liver?
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Neutrophils
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Macrophages
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Kupffer cells
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Eosinophils
C
Correct answer
Explanation
Kupffer cells are specialized macrophages found in the liver. They play a crucial role in phagocytosing pathogens, cellular debris, and foreign particles in the liver.
What is the role of cytokines in phagocytosis?
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They activate complement proteins
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They bind to pathogens and enhance phagocytosis
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They produce antibodies
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They regulate the activity of phagocytes
D
Correct answer
Explanation
Cytokines are small proteins that regulate the activity of phagocytes. They can stimulate phagocytosis, enhance the killing ability of phagocytes, and promote the recruitment of other immune cells to the site of infection.
Which of the following is a type of phagocytic cell found in the brain?
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Neutrophils
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Macrophages
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Microglia
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Eosinophils
C
Correct answer
Explanation
Microglia are specialized macrophages found in the brain and spinal cord. They play a crucial role in phagocytosing pathogens, cellular debris, and foreign particles in the central nervous system.
What is the role of neutrophils in phagocytosis?
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They are the primary phagocytes in the blood
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They are tissue-resident phagocytes
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They produce antibodies
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They release histamine
A
Correct answer
Explanation
Neutrophils are the most abundant type of phagocytes in the blood and are the primary cells responsible for phagocytosis during the early stages of an immune response.