Introduction to Immunology Flashcards
Basic components of Immune System
What is the primary function of the innate immune system?
To provide immediate, non-specific defense against pathogens.
True or False: The adaptive immune system develops memory cells after an infection.
True
What type of response does the innate immune system initiate?
A rapid response.
Fill in the blank: The innate immune system includes physical barriers such as _____ and _____ .
skin, mucous membranes
Which cells are primarily involved in the adaptive immune response?
Lymphocytes (B cells and T cells).
What is a key characteristic of adaptive immunity?
Specificity for particular pathogens.
Multiple Choice: Which of the following is NOT a component of the innate immune system? A) Macrophages B) T cells C) Neutrophils D) Natural killer cells
B) T cells
What type of immunity is conferred by vaccination?
Adaptive immunity.
True or False: The innate immune system has a slower response time compared to the adaptive immune system.
False
What is the role of phagocytes in the innate immune system?
To engulf and destroy pathogens.
Fill in the blank: The adaptive immune system is characterized by _____ and _____ .
memory, specificity
Which type of T cell helps activate B cells?
Helper T cells.
Multiple Choice: Which of the following is part of the innate immune response? A) Antibody production B) Inflammation C) Clonal expansion D) Antigen presentation
B) Inflammation
What type of cell is responsible for producing antibodies?
B cells.
True or False: The innate immune system can recognize a wide range of pathogens.
True
What is the function of natural killer (NK) cells?
To destroy infected or cancerous cells.
Fill in the blank: The adaptive immune response can take _____ to develop after initial exposure to a pathogen.
days to weeks
What is the main difference between humoral and cell-mediated immunity?
Humoral immunity involves antibodies, while cell-mediated immunity involves T cells.
Multiple Choice: Which of the following acts as a bridge between the innate and adaptive immune systems? A) Antibodies B) Dendritic cells C) Phagocytes D) Cytokines
B) Dendritic cells
True or False: The innate immune response is always the same regardless of the pathogen.
True
What are cytokines?
Signaling molecules that mediate and regulate immunity and inflammation.
Fill in the blank: The adaptive immune system generates a _____ response upon subsequent exposures to the same pathogen.
faster and stronger
What role do memory cells play in the adaptive immune system?
They provide long-lasting immunity by responding quickly to previously encountered pathogens.
Multiple Choice: Which immune system component is responsible for directly killing infected cells? A) B cells B) Helper T cells C) Cytotoxic T cells D) Antibodies
C) Cytotoxic T cells
True or False: The innate immune system can adapt to new pathogens.
False
What is the term for the process by which B cells produce antibodies?
Clonal selection and expansion.
What is passive immunity?
Passive immunity is the immunity acquired through the transfer of antibodies from one individual to another.
What is active immunity?
Active immunity is the immunity that develops as a result of exposure to an antigen, leading to the production of antibodies by the immune system.
True or False: Passive immunity provides immediate protection.
True
True or False: Active immunity develops slowly over time.
True
Fill in the blank: Passive immunity can be acquired naturally through _______.
breastfeeding
Fill in the blank: Active immunity can be acquired through _______.
vaccination
What is an example of passive immunity?
An example of passive immunity is the transfer of maternal antibodies to a fetus during pregnancy.
What is an example of active immunity?
An example of active immunity is the immune response generated after receiving a vaccine.
Which type of immunity has a longer duration of protection, active or passive?
Active immunity has a longer duration of protection.
What is the main difference in the source of antibodies between passive and active immunity?
In passive immunity, antibodies come from an external source; in active immunity, antibodies are produced by the individual’s own immune system.
Multiple Choice: Which of the following is a characteristic of passive immunity? A) Slow onset B) Long-lasting C) Immediate protection D) Requires exposure to antigen
C) Immediate protection
Multiple Choice: Which of the following is a characteristic of active immunity? A) Short-lived B) Immediate protection C) Developed after infection D) None of the above
C) Developed after infection
True or False: Passive immunity requires the immune system to be activated.
False
What is a potential disadvantage of passive immunity?
A potential disadvantage of passive immunity is that it does not provide long-term protection.
What type of immunity might a newborn receive from its mother?
A newborn receives passive immunity from its mother.
What is one way active immunity can be artificially acquired?
Active immunity can be artificially acquired through vaccination.
Fill in the blank: The antibodies in passive immunity are typically obtained from _______.
another person or animal
What is the role of memory cells in active immunity?
Memory cells help the immune system respond more quickly and effectively upon subsequent exposures to the same antigen.
Multiple Choice: Which type of immunity can be developed after recovering from an infection? A) Passive B) Active C) Both D) Neither
B) Active
True or False: Immunoglobulin therapy is an example of passive immunity.
True
What is the primary method of acquiring passive immunity in infants?
The primary method is through breastfeeding.
Fill in the blank: The duration of passive immunity is generally _______ than that of active immunity.
shorter
What can stimulate the production of antibodies in active immunity?
Exposure to pathogens or vaccination can stimulate the production of antibodies.
Multiple Choice: Which type of immunity is characterized by a faster response to pathogens? A) Passive B) Active C) Both D) Neither
A) Passive
What is one reason why active immunity is considered more beneficial in the long term?
Active immunity provides lasting protection through memory cells.
What is the primary immune response?
The primary immune response is the initial response of the immune system to a specific antigen, characterized by the activation of naive B and T lymphocytes.
What is the secondary immune response?
The secondary immune response is the immune system’s response to a previously encountered antigen, resulting in a faster and more robust reaction.
True or False: The primary immune response occurs faster than the secondary immune response.
False
Fill in the blank: The primary immune response typically takes ______ days to develop.
7-14
Fill in the blank: The secondary immune response typically takes ______ days to develop.
1-3
What type of immune cells are primarily involved in the primary immune response?
Naive B and T lymphocytes
What type of immune cells are primarily involved in the secondary immune response?
Memory B and T lymphocytes
Which antibody is most commonly produced during the primary immune response?
IgM
Which antibody is most commonly produced during the secondary immune response?
IgG
True or False: The secondary immune response has a higher affinity for the antigen compared to the primary response.
True
What is the role of memory cells in the immune response?
Memory cells provide a quicker and stronger response upon re-exposure to the same antigen.
How does the duration of antibody production compare between primary and secondary immune responses?
Antibody production lasts longer in the secondary immune response.
What is the significance of the lag phase in the primary immune response?
The lag phase represents the time taken for B and T cells to be activated and proliferate before antibodies are produced.
What is a characteristic feature of the memory response in the secondary immune response?
A quicker rise in antibody levels.
Multiple Choice: Which of the following is NOT a feature of the primary immune response? A) Slower activation B) Memory cells present C) IgM production D) Initial exposure
B) Memory cells present
Fill in the blank: The primary immune response is characterized by the generation of ______ cells.
naive
Fill in the blank: The secondary immune response results in the production of ______ specific antibodies.
high-affinity
What happens to the number of antibodies produced during the secondary immune response compared to the primary response?
The number of antibodies produced is significantly higher in the secondary response.
True or False: Vaccination primarily relies on the secondary immune response for long-term immunity.
True
What is the impact of repeated exposure to the same antigen on the secondary immune response?
Repeated exposure leads to an increasingly stronger and quicker secondary immune response.
Multiple Choice: Which of the following factors influences the effectiveness of the primary immune response? A) Type of antigen B) Previous exposure C) Age D) All of the above
D) All of the above
What is the effect of antigen persistence on the immune response?
Antigen persistence can prolong the immune response and enhance memory cell formation.
Fill in the blank: The memory phase of the immune response is essential for ______ immunity.
adaptive
True or False: The primary immune response can lead to the development of memory cells.
True
What is the role of helper T cells in the immune response?
Helper T cells assist in activating B cells and cytotoxic T cells during both primary and secondary responses.
What is the primary function of B lymphocytes?
To produce antibodies.
True or False: T lymphocytes are primarily involved in humoral immunity.
False.
Fill in the blank: B lymphocytes develop in the ________.
Bone marrow.
What type of immunity do T lymphocytes primarily mediate?
Cell-mediated immunity.
What is the main morphologic feature of activated B lymphocytes?
They become larger and more irregular in shape.
Which surface marker is commonly found on B lymphocytes?
CD19.
What are memory T cells responsible for?
Providing long-term immunity by quickly responding to previously encountered antigens.
True or False: Both B and T lymphocytes originate from the same type of progenitor cell.
True.
What is the role of helper T cells (CD4+ T cells)?
To assist other immune cells by releasing cytokines.
Fill in the blank: T lymphocytes mature in the ________.
Thymus.
What is the significance of the immunoglobulin receptor on B lymphocytes?
It allows B cells to recognize specific antigens.
What are the two main types of T lymphocytes?
Helper T cells and cytotoxic T cells.
Which lymphocyte is primarily responsible for killing infected cells?
Cytotoxic T cells.
True or False: B cells undergo somatic hypermutation to increase antibody affinity.
True.
What is the process by which B cells differentiate into plasma cells?
Activation and clonal expansion.
Fill in the blank: T cells recognize antigens presented by ________ molecules.
MHC (Major Histocompatibility Complex).
What is the primary function of regulatory T cells?
To maintain immune tolerance and prevent autoimmune responses.
Which cytokine is primarily produced by Th1 cells?
Interferon-gamma (IFN-γ).
What morphologic change occurs in T lymphocytes upon activation?
Increased size and expression of activation markers.
Fill in the blank: The interaction between B cells and ________ cells is crucial for B cell activation.
Helper T.
What type of antibodies do plasma cells produce?
Immunoglobulins (Ig).
True or False: Naive T cells can directly kill infected cells.
False.
What is the role of antigen-presenting cells (APCs) in relation to T lymphocytes?
To present antigens to T cells for activation.
Which type of T cell is involved in helping B cells produce antibodies?
Helper T cells.
What is the primary morphologic characteristic of memory B cells?
They have a smaller size compared to plasma cells.
Fill in the blank: B cells primarily respond to ________ antigens.
Extracellular.
What is one key function of cytokines released by activated T cells?
To regulate the immune response.
What is the primary function of natural killer (NK) cells?
To identify and destroy infected or cancerous cells.
True or False: Neutrophils are primarily involved in the adaptive immune response.
False.
Fill in the blank: Natural killer cells are a type of __________ immune cell.
innate.
What is the main morphological feature of neutrophils?
Multilobed nucleus.
Which cell type is characterized by large granules in their cytoplasm?
Neutrophils.
What cytokine is primarily produced by NK cells?
Interferon-gamma (IFN-γ).
Multiple Choice: Which of the following is NOT a function of neutrophils? A) Phagocytosis B) Antibody production C) Degranulation
B) Antibody production.
True or False: NK cells can directly kill target cells without prior sensitization.
True.
What is the lifespan of neutrophils in the bloodstream?
A few hours to a few days.
Fill in the blank: Natural killer cells recognize infected cells through __________ receptors.
activating.
What is the role of chemotactic factors in neutrophil function?
They attract neutrophils to sites of infection.
Which type of cell is primarily responsible for the rapid response to infection?
Neutrophils.
Multiple Choice: What is the primary mechanism by which NK cells kill infected cells? A) Phagocytosis B) Cytotoxic granule release C) Antibody-dependent cell-mediated cytotoxicity
B) Cytotoxic granule release.
True or False: Neutrophils can undergo apoptosis after performing their function.
True.
What is the main purpose of NK cell activation?
To enhance their ability to kill target cells.
Fill in the blank: Neutrophils are derived from __________ in the bone marrow.
myeloid progenitors.
What surface marker is commonly associated with NK cells?
CD56.
Multiple Choice: Which of the following is a characteristic of NK cells? A) Presence of T-cell receptors B) Ability to produce antibodies C) Expression of CD16
C) Expression of CD16.
What kind of granules do neutrophils contain?
Specific and azurophilic granules.
True or False: Natural killer cells play a role in tumor surveillance.
True.
What is the primary method by which neutrophils kill pathogens?
Phagocytosis.
Fill in the blank: NK cells are part of the __________ immune system.
innate.
What is the function of perforin produced by NK cells?
To create pores in the target cell membrane.
Multiple Choice: Which cytokine is crucial for neutrophil recruitment? A) IL-10 B) IL-6 C) IL-8
C) IL-8.
What does degranulation in neutrophils release?
Enzymes and antimicrobial substances.
True or False: Both NK cells and neutrophils originate from the same progenitor cell type.
False.
What is the primary function of mast cells in the immune system?
Mast cells play a crucial role in allergic reactions and defense against pathogens by releasing histamine and other mediators.
True or False: Eosinophils are primarily involved in combating parasitic infections.
True
Fill in the blank: Monocytes differentiate into __________ when they migrate into tissues.
macrophages
What is a key morphologic feature of mast cells?
Mast cells contain granules filled with histamine and other inflammatory mediators.
Multiple Choice: Which of the following is NOT a function of eosinophils? A) Phagocytosis B) Release of cytotoxic granules C) Antigen presentation D) Modulating allergic responses
C) Antigen presentation
What is the lifespan of monocytes in circulation before they migrate to tissues?
Monocytes typically circulate for about 1-3 days.
True or False: Mast cells are derived from the same precursor as basophils.
True
What type of receptors do mast cells express that are important for their activation?
Mast cells express high-affinity IgE receptors (FcεRI).
Short Answer: What are the two main types of granules found in eosinophils?
Major basic protein and eosinophil peroxidase.
Multiple Choice: Which cytokine is primarily produced by activated eosinophils? A) IL-4 B) IL-5 C) IL-6 D) TNF-alpha
B) IL-5
Fill in the blank: The primary role of monocytes in the immune response is __________.
phagocytosis
What is the function of histamine released by mast cells?
Histamine increases vascular permeability and causes smooth muscle contraction.
True or False: Eosinophils are primarily involved in the response to bacterial infections.
False
Short Answer: What is the typical diameter range of a human eosinophil?
10-15 micrometers.
What are the morphological characteristics of monocytes?
Monocytes are large cells with a kidney-shaped nucleus and abundant cytoplasm.
Multiple Choice: Which of the following conditions is associated with mast cell activation? A) Asthma B) Diabetes C) Hypertension D) Osteoporosis
A) Asthma
Fill in the blank: Eosinophils are primarily produced in the __________.
bone marrow
True or False: Mast cells can be found in tissues throughout the body, including the skin and mucosal surfaces.
True
What role do eosinophils play in allergic reactions?
Eosinophils contribute to the inflammatory response and tissue damage in allergic reactions.
Short Answer: What are the two primary types of mast cells?
Mucosal mast cells and connective tissue mast cells.
Multiple Choice: Which of the following is a common trigger for mast cell degranulation? A) Bacterial toxins B) Allergens C) Viral infections D) All of the above
D) All of the above
Fill in the blank: The presence of __________ is a defining characteristic of eosinophils.
eosinophilic granules
True or False: Monocytes can also differentiate into dendritic cells.
True
What is the primary function of macrophages derived from monocytes?
Macrophages are responsible for phagocytosing pathogens and dead cells.
What are macrophages primarily responsible for?
Phagocytosis and immune response.
True or False: Dendritic cells are primarily involved in the adaptive immune response.
True.
Fill in the blank: Macrophages originate from __________.
Monocytes.
What morphological feature distinguishes dendritic cells from macrophages?
Dendritic cells have long, thin projections called dendrites.
Which type of immune cell is known for antigen presentation?
Dendritic cells.
Multiple Choice: Which of the following is a function of macrophages? A) Antigen presentation B) Phagocytosis C) Cytokine secretion D) All of the above
D) All of the above.
What is the main role of macrophage cytokines?
To mediate immune responses and inflammation.
True or False: Dendritic cells can activate T cells.
True.
Fill in the blank: The process by which macrophages engulf and digest cellular debris is called __________.
Phagocytosis.
What is the primary location of dendritic cells in the body?
Tissues and lymphoid organs.
Multiple Choice: Which cell type is primarily responsible for the innate immune response? A) T cells B) B cells C) Macrophages D) Dendritic cells
C) Macrophages.
What is the lifespan of macrophages in tissues?
They can live for several months to years.
True or False: Dendritic cells are capable of self-renewal.
False.
What are the two main types of dendritic cells?
Conventional dendritic cells and plasmacytoid dendritic cells.
Fill in the blank: The surface receptors on macrophages that recognize pathogens are called __________.
Pattern recognition receptors (PRRs).
What role do dendritic cells play in linking innate and adaptive immunity?
They capture and present antigens to T cells.
Multiple Choice: Which cytokine is primarily produced by activated macrophages? A) IL-2 B) IL-6 C) IFN-γ D) TNF-α
D) TNF-α.
What triggers the activation of macrophages?
Recognition of pathogens or inflammatory signals.
True or False: Dendritic cells can migrate to lymph nodes after antigen capture.
True.
What is the primary function of plasmacytoid dendritic cells?
Production of type I interferons in response to viruses.
Fill in the blank: Macrophages can be classified into __________ and __________ based on their activation state.
M1 and M2.
What morphological change occurs in macrophages when activated?
Increased size and changes in shape.
Multiple Choice: Which of the following is NOT a function of macrophages? A) Antigen processing B) Phagocytosis C) Antibody production D) Cytokine secretion
C) Antibody production.
What is the primary role of M2 macrophages?
Tissue repair and anti-inflammatory responses.
True or False: Dendritic cells are found in high numbers in the bloodstream.
False.
What type of immunity do macrophages predominantly participate in?
Innate immunity.
