Leukocytes: Classification, Morphology, and Functions

Question 1

Which type of leukocyte is primarily responsible for presenting processed antigens to T cells?

Accepted Answer

Dendritic cell

Answer

Neutrophil

Answer

Macrophage

Answer

Lymphocyte

Question 2

What is the primary function of macrophages in the immune system?

Accepted Answer

Phagocytosis and antigen presentation

Answer

Antibody production

Answer

Cell-mediated immunity

Answer

Antigen presentation only

Question 3

Which type of lymphocyte is responsible for producing antibodies?

Accepted Answer

B cell

Answer

T cell

Answer

Natural killer cell

Answer

Dendritic cell

Question 4

What is the unique feature of dendritic cells that enables their efficient antigen presentation?

Accepted Answer

Large amounts of MHC Class II molecules

Answer

Motile nature

Answer

Phagocytic capability

Answer

Ability to secrete cytokines

Question 5

Which of the following is a mechanism by which leukocytes are recruited to a site of infection?

Accepted Answer

Chemotaxis

Answer

Opsonization

Answer

Complement activation

Answer

Antibody-mediated cytotoxicity

Question 6

What is the primary role of cytokines in leukocyte function?

Accepted Answer

Cell signaling and activation

Answer

Antigen recognition

Answer

Antibody production

Answer

Phagocytosis enhancement

Question 7

Which leukocyte subset is primarily involved in the adaptive immune response?

Accepted Answer

Lymphocytes

Answer

Neutrophils

Answer

Macrophages

Answer

Dendritic cells

Question 8

What is the key difference between myeloid and lymphoid progenitor cells?

Accepted Answer

Myeloid progenitors give rise to granulocytes and monocytes, while lymphoid progenitors give rise to lymphocytes

Answer

Myeloid progenitors give rise to lymphocytes, while lymphoid progenitors give rise to granulocytes and monocytes

Answer

Myeloid and lymphoid progenitor cells have the same developmental potential

Answer

Myeloid progenitors are found in the bone marrow, while lymphoid progenitors are found in the spleen

Question 9

Which of the following is a primary function of eosinophils?

Accepted Answer

Defense against parasitic infections

Answer

Phagocytosis of bacteria

Answer

Antigen presentation

Answer

Production of antibodies

Question 10

Which of the following is a distinct characteristic of neutrophils?

Accepted Answer

Polymorphonuclear shape

Answer

Fixed in tissues

Answer

Antibody production

Answer

Dendritic morphology

Question 11

Which leukocyte type specializes in presenting antigens to the immune system?

Accepted Answer

Dendritic cell

Answer

Neutrophil

Answer

Macrophage

Answer

T cell

Question 12

What is the primary function of macrophages within the immune system?

Accepted Answer

Engulfing and destroying foreign particles

Answer

Producing antibodies

Answer

Initiating adaptive immune responses

Answer

Releasing cytokines

Question 13

Which cell type plays a crucial role in initiating adaptive immune responses?

Accepted Answer

Dendritic cell

Answer

Neutrophil

Answer

Macrophage

Answer

B cell

Question 14

Which leukocyte type is most prevalent in the bloodstream?

Accepted Answer

Neutrophil

Answer

Macrophage

Answer

Lymphocyte

Answer

Dendritic cell

Question 15

Which characteristic is associated with plasma cells?

Accepted Answer

Antibody secretion

Answer

Longevity

Answer

Phagocytosis

Answer

High motility

Question 16

Which leukocyte type is responsible for producing interferons?

Accepted Answer

Lymphocyte

Answer

Neutrophil

Answer

Macrophage

Answer

Dendritic cell

Question 17

What is the primary function of dendritic cells in the immune response?

Accepted Answer

Presenting antigens to T cells, initiating adaptive immune responses

Answer

Phagocytizing and killing pathogens

Answer

Producing antibodies to neutralize pathogens

Answer

Secreting cytokines that regulate immune cell activity

Question 18

Which of the following correctly classifies leukocytes into their two primary cell lineages?

Accepted Answer

Myeloid: Neutrophils, Macrophages; Lymphoid: Lymphocytes

Answer

Myeloid: Lymphocytes, Macrophages; Lymphoid: Neutrophils

Answer

Myeloid: Neutrophils, Lymphocytes; Lymphoid: Macrophages

Question 19

Leukocyte counts and differentials play a crucial role in diagnosing and monitoring various disease conditions. Explain their clinical significance in this context.

Accepted Answer

Leukocyte counts and differentials offer valuable insights into a wide range of disease states, including infections, inflammatory conditions, and hematological malignancies.

Answer

Leukocyte counts and differentials are exclusively useful in diagnosing infectious diseases.

Answer

Leukocytosis (elevated leukocyte count) is a definitive indicator of bacterial infection.

Answer

Lymphopenia (decreased lymphocyte count) is exclusively associated with viral infections.

Question 20

Identify the type of leukocyte most abundant in the body, known for its crucial role in phagocytosing bacteria and fungi.

Accepted Answer

Neutrophils

Answer

Macrophages

Answer

Lymphocytes

Answer

Dendritic cells

Question 21

Which of the following accurately describes the distinctive nuclear morphology observed in macrophages?

Accepted Answer

Irregularly shaped nucleus

Answer

Segmented nucleus

Answer

Bilobed nucleus

Answer

Round nucleus

Question 22

Identify the type of lymphocyte primarily responsible for producing antibodies, a critical component of antibody-mediated immunity.

Accepted Answer

B cells

Answer

T cells

Answer

Natural killer cells

Answer

Dendritic cells

Question 23

Which cell type serves as the primary antigen-presenting cell, playing a crucial role in initiating T cell responses?

Accepted Answer

Dendritic cells

Answer

Neutrophils

Answer

Macrophages

Answer

Lymphocytes

Question 24

Which type of macrophage is specifically found in the liver and spleen, performing specialized functions in these organs?

Accepted Answer

Kupffer cells

Answer

Microglia

Answer

Osteoclasts

Answer

Langerhans cells

Question 25

Identify the key function of dendritic cells, which distinguishes them from other leukocyte types and makes them crucial for immune surveillance.

Accepted Answer

Presenting antigens to lymphocytes

Answer

Phagocytosing pathogens

Answer

Releasing inflammatory mediators

Answer

Producing antibodies

Question 26

Which type of lymphocyte is responsible for orchestrating cell-mediated immunity, directly targeting and eliminating infected cells?

Accepted Answer

T cells

Answer

B cells

Answer

Natural killer cells

Answer

Dendritic cells

Question 27

Neutrophils are primarily responsible for the elimination of which type of pathogen?

Accepted Answer

Bacteria

Answer

Viruses

Answer

Fungi

Answer

Parasites

Question 28

Which type of leukocyte is characterized by a large, bean-shaped nucleus and abundant cytoplasm?

Accepted Answer

Macrophage

Answer

Neutrophil

Answer

Lymphocyte

Answer

Dendritic cell

Question 29

What is a crucial role played by dendritic cells?

Accepted Answer

Activating T cells

Answer

Producing antibodies

Answer

Phagocytosing pathogens

Answer

Complement activation

Question 30

Which leukocyte type is responsible for secreting antibodies against specific antigens?

Accepted Answer

B cell

Answer

Neutrophil

Answer

Macrophage

Answer

Dendritic cell

Question 31

The process by which macrophages engulf and destroy foreign particles is technically referred to as:

Accepted Answer

Phagocytosis

Answer

Chemotaxis

Answer

Opsonization

Answer

Cytokine release

Question 32

Which of the following is not a characteristic of neutrophils?

Accepted Answer

Short-lived (hours to days)

Answer

Lobed nucleus

Answer

Phagocytic

Answer

Highly motile

Question 33

Which type of lymphocyte is responsible for cell-mediated immunity?

Accepted Answer

T cell

Answer

B cell

Answer

Natural killer cell

Answer

Dendritic cell

Question 34

Dendritic cells are specialized antigen-presenting cells that play a crucial role in:

Accepted Answer

Initiating adaptive immune responses

Answer

Phagocytosing pathogens

Answer

Releasing inflammatory cytokines

Answer

Producing antibodies

Question 35

A patient with a bacterial infection is likely to have elevated levels of:

Accepted Answer

Neutrophils

Answer

Macrophages

Answer

Eosinophils

Answer

Natural killer cells

Question 36

Which of the following techniques is commonly used to identify and differentiate leukocytes?

Accepted Answer

Flow cytometry

Answer

Immunohistochemistry

Answer

Electron microscopy

Answer

Polymerase chain reaction

Question 37

Which of the following disorders is characterized by a deficiency in neutrophil function?

Accepted Answer

Chronic granulomatous disease

Answer

Anemia

Answer

Leukemia

Answer

Thrombocytopenia

Question 38

Classify the different lymphocyte subsets (B cells, T cells, and natural killer (NK) cells) and elucidate their unique functions within the immune system.

Accepted Answer

B cells produce antibodies, T cells mediate cellular immunity, and NK cells eliminate virus-infected cells.

Answer

B cells produce antibodies, T cells eliminate virus-infected cells, and NK cells mediate cellular immunity.

Answer

T cells produce antibodies, B cells mediate cellular immunity, and NK cells eliminate bacteria-infected cells.

Answer

T cells produce antibodies, NK cells eliminate virus-infected cells, and B cells mediate cellular immunity.

Question 39

What is the primary function of neutrophils in the immune system?

Accepted Answer

Engulfing and destroying foreign particles

Answer

Producing antibodies

Answer

Presenting antigens to other immune cells

Answer

Developing into memory cells

Question 40

Which of the following cell types is **NOT** a granulocyte?

Accepted Answer

Lymphocyte

Answer

Neutrophil

Answer

Eosinophil

Answer

Basophil

Question 41

What is the **primary** function of macrophages?

Accepted Answer

Phagocytosis

Answer

Antibody production

Answer

Cytotoxicity

Answer

Antigen presentation

Question 42

Which type of lymphocyte is responsible for cell-mediated immunity?

Accepted Answer

T lymphocyte

Answer

Dendritic cell

Answer

Natural killer cell

Answer

B lymphocyte

Question 43

What is the **main** role of dendritic cells in the immune system?

Accepted Answer

Antigen presentation

Answer

Antibody production

Answer

Phagocytosis

Answer

Cytotoxicity

Question 44

Which type of leukocyte is the most abundant circulating leukocyte in the blood?

Accepted Answer

Neutrophil

Answer

Eosinophil

Answer

Lymphocyte

Answer

Monocyte

Question 45

Which of the following is a **primary** function of eosinophils?

Accepted Answer

Defense against parasitic infections

Answer

Antibody production

Answer

Phagocytosis

Question 46

Which of the following is a characteristic of basophils?

Accepted Answer

Secretion of histamine

Answer

Phagocytic activity

Answer

High mobility

Answer

Production of antibodies

Question 47

What is the **main** function of monocytes in the immune system?

Accepted Answer

Differentiation into macrophages

Answer

Antibody production

Answer

Antigen presentation

Answer

Cytotoxicity

Question 48

Which leukocyte population is primarily responsible for mediating cell-mediated immunity?

Accepted Answer

Lymphocytes

Answer

Macrophages

Answer

Neutrophils

Answer

Dendritic cells

Question 49

Which leukocyte has a multi-lobed nucleus and is the most abundant type in the bloodstream?

Accepted Answer

Neutrophils

Answer

Lymphocytes

Answer

Eosinophils

Answer

Basophils

Question 50

Which of the following is NOT a type of lymphocyte?

Accepted Answer

Monocytes

Answer

NK cells

Answer

B cells

Answer

T cells

Question 51

Which type of leukocyte releases histamine and plays a key role in allergic reactions?

Accepted Answer

Basophils

Answer

Macrophages

Answer

Eosinophils

Answer

Neutrophils

Question 52

Which leukocyte population is known for its ability to undergo clonal expansion and produce antibodies?

Accepted Answer

B cells

Answer

T cells

Answer

Macrophages

Answer

NK cells

Question 53

Which type of leukocyte releases cytotoxic granules and plays a crucial role in killing tumor cells?

Accepted Answer

NK cells

Answer

T cells

Answer

Dendritic cells

Answer

B cells

Question 54

Which leukocyte population is primarily found in lymphoid tissues and is responsible for mediating cellular immune responses?

Accepted Answer

T cells

Answer

Macrophages

Answer

B cells

Answer

NK cells