Cells of the Innate Immune System Quiz: Test Your Knowledge

Question 1

Which type of innate immune cell releases cytotoxic granules that can directly kill infected cells?

Accepted Answer

Natural killer cells

Answer

Neutrophils

Answer

Macrophages

Answer

Dendritic cells

Question 2

Which of the following characteristics is unique to neutrophils?

Accepted Answer

Ability to release neutrophil extracellular traps (NETs)

Answer

High phagocytic capacity

Answer

Expression of MHC class II molecules

Answer

Long lifespan

Question 3

What is the primary role of pattern recognition receptors (PRRs) in innate immunity?

Accepted Answer

Recognition of pathogens and danger signals

Answer

Activation of adaptive immune responses

Answer

Phagocytosis of pathogens

Answer

Production of antibodies

Question 4

What is the primary function of complement proteins in innate immunity?

Accepted Answer

Opsonization and phagocytosis of pathogens

Answer

Activation of the adaptive immune system

Answer

Direct killing of pathogens

Answer

Regulation of inflammation

Question 5

Which of the following cytokines is a key mediator of the inflammatory response?

Accepted Answer

Interleukin-1

Answer

Interleukin-2

Answer

Interferon-γ

Answer

Transforming growth factor-β

Question 6

What is the overall purpose of the complement cascade in innate immunity?

Accepted Answer

To identify and eliminate pathogens

Answer

To activate the adaptive immune system

Answer

To regulate inflammation

Answer

To recruit immune cells to the site of infection

Question 7

Which biological process involves attracting immune cells, increasing blood flow, and repairing tissue at the site of infection or injury?

Accepted Answer

Inflammation

Answer

Adaptive immunity

Answer

Phagocytosis

Answer

Antigen presentation

Question 8

Which of the following is NOT a key function of neutrophils in innate immunity?

Accepted Answer

Antigen presentation to T cells

Answer

Phagocytosis of bacteria

Answer

Release of antimicrobial peptides

Answer

Killing of infected cells

Question 9

Macrophages arise from which of the following precursor cells?

Accepted Answer

Monocytes

Answer

Neutrophils

Answer

Dendritic cells

Answer

Natural killer cells

Question 10

Which receptor is primarily involved in the recognition of pathogen-associated molecular patterns (PAMPs) on macrophages?

Accepted Answer

Toll-like receptor (TLR)

Answer

Fc receptor

Answer

Complement receptor

Answer

Mannose receptor

Question 11

Dendritic cells are specialized in:

Accepted Answer

Antigen presentation to T cells

Answer

Phagocytosis

Answer

Killing of infected cells

Answer

Antibody production

Question 12

Which cytokine is primarily responsible for the activation of natural killer cells?

Accepted Answer

Interferon-γ (IFN-γ)

Answer

Interleukin-2 (IL-2)

Answer

Tumor necrosis factor (TNF)

Answer

Transforming growth factor-β (TGF-β)

Question 13

Which of the following is NOT a common mechanism of innate immune evasion by pathogens?

Accepted Answer

Antibiotic resistance

Answer

Molecular mimicry

Answer

Antigenic variation

Answer

Immunosuppression

Question 14

Which cell type is primarily responsible for phagocytosing pathogens and cellular debris?

Accepted Answer

Macrophages

Answer

Neutrophils

Answer

Dendritic cells

Answer

Natural killer cells

Question 15

Which cell type is primarily responsible for initiating adaptive immune responses by presenting antigens to T cells?

Accepted Answer

Dendritic cells

Answer

Neutrophils

Answer

Macrophages

Answer

Natural killer cells

Question 16

Which type of innate immune cell is known for its ability to rapidly migrate to sites of infection and release antimicrobial substances?

Accepted Answer

Neutrophils

Answer

Macrophages

Answer

Dendritic cells

Answer

Natural killer cells

Question 17

Which of the following is a key component of the complement system, a group of proteins involved in innate immune responses?

Accepted Answer

C3b

Answer

Immunoglobulin G (IgG)

Answer

Interferon-γ

Answer

Tumor necrosis factor-α

Question 18

Which type of innate immune response involves non-specific binding and lysis of pathogens?

Accepted Answer

Natural cytotoxicity

Answer

Opsonization

Answer

Phagocytosis

Answer

Inflammation

Question 19

Which of the following cytokines is primarily involved in activating macrophages and neutrophils during innate immune responses?

Accepted Answer

Interleukin-1β

Answer

Interleukin-10

Answer

Interferon-α

Answer

Tumor necrosis factor-α

Question 20

Which innate immune cell type is essential for presenting antigens to T cells, initiating adaptive immune responses?

Accepted Answer

Dendritic cell

Answer

Macrophage

Answer

Natural killer cell

Answer

Neutrophil

Question 21

Which cell directly eliminates infected or cancerous cells by releasing cytotoxic granules and cytokines?

Accepted Answer

Natural killer cell

Answer

Dendritic cell

Answer

Macrophage

Answer

Neutrophil

Question 22

Which of these is the most abundant phagocytic white blood cell, characterized by a multi-lobed nucleus and granules?

Accepted Answer

Neutrophil

Answer

Macrophage

Answer

Dendritic cell

Question 23

Which of the following accurately describes an innate immune response?

Accepted Answer

Rapid and non-specific

Answer

Slow and antigen-specific

Answer

Targets only intracellular pathogens

Answer

Involves memory cells

Question 24

Which cell type is primarily responsible for releasing pro-inflammatory cytokines like TNF-α and IL-1β, initiating and coordinating the inflammatory response?

Accepted Answer

Macrophage

Answer

Dendritic cell

Answer

Natural killer cell

Answer

Neutrophil

Question 25

Which toll-like receptor (TLR) specifically recognizes bacterial lipopolysaccharide (LPS)?

Accepted Answer

TLR4

Answer

TLR2

Answer

TLR3

Answer

TLR7