Question 1

Which of the following are not considered to be part of innate immunity?&#10;A) Neutrophils&#10;B) Monocytes&#10;C) T lymphocytes&#10;D) Natural killer cells&#10;E) Complement proteins

Accepted Answer

T lymphocytes are part of adaptive immunity. Innate immunity includes neutrophils, monocytes, natural killer cells, and complement proteins.

Question 2

Which of the following are the most numerous leukocytes in blood?&#10;A) Natural killer cells&#10;B) Neutrophils&#10;C) Monocytes&#10;D) Lymphocytes&#10;E) Basophil

Accepted Answer

Neutrophils are the most numerous leukocytes in the blood, making up approximately 50-70% of all leukocytes.

Question 3

Macrophages and dendritic cells present antigens to which of the following...&#10;A) Neutrophils&#10;B) Natural Killer cells&#10;C) T lymphocytes&#10;D) B lymphocytes&#10;E) Plasma cells

Accepted Answer

Macrophages and dendritic cells are antigen-presenting cells that display fragments of foreign antigens in a complex with major histocompatibility complex (MHC) molecules on their surface. T lymphocytes recognize these foreign antigens presented by the MHC molecules and initiate an immune response. Therefore, the correct answer is C, T lymphocytes.

Question 4

Toll-like receptors are involved in...&#10;A) Recognition of pathogens&#10;B) Activation of phagocytosis&#10;C) Antigen presentation&#10;D) Antibody formation&#10;E) Interactions between antigen-presenting cells and other leukocytes

Accepted Answer

Toll-like receptors are a type of pattern recognition receptor that recognize pathogen-associated molecular patterns (PAMPs) and play a key role in the innate immune response by triggering the production of cytokines and chemokines that initiate inflammation and activate adaptive immunity.

Question 5

The main effector cells of cell-mediated immunity are...&#10;A) Neutrophils&#10;B) Monocytes&#10;C) T-helper lymphocytes&#10;D) T-cytotoxic lymphocytes&#10;E) Natural killer cells

Accepted Answer

T-cytotoxic lymphocytes, also known as T-killer cells, are the main effector cells of cell-mediated immunity. They are crucial in identifying and destroying infected or abnormal cells in the body. Neutrophils and monocytes are phagocytic cells involved in innate immunity, while T-helper lymphocytes help activate other immune cells. Natural killer cells are part of innate immunity and also kill infected cells, but they do not require previous exposure to a foreign antigen.

Question 6

Which of the following is not a subclass of the immunoglobulins?&#10;A) IgA&#10;B) IgB&#10;C) IgE&#10;D) IgG&#10;E) IgM

Accepted Answer

IgB is not a subclass of immunoglobulins. It does not exist as an immunoglobulin class.

Question 7

Which of the following cells exhibit immunological memory?&#10;A) Neutrophils and monocytes&#10;B) Macrophages and dendritic cells&#10;C) T and B lymphocytes&#10;D) Basophils and eosinophils&#10;E) Thymus and bone marrow cells

Accepted Answer

T and B lymphocytes exhibit immunological memory. They can recognize and respond to specific antigens they have encountered before, leading to a faster and more effective immune response upon subsequent exposure to the same pathogen.

Question 8

Th2 cytokines are involved in the activation of...&#10;A) Phagocytosis&#10;B) Antigen presentation&#10;C) Innate immunity&#10;D) Cell-mediated immunity&#10;E) Humoral immunity

Accepted Answer

Th2 cytokines are primarily involved in the activation of B cells, which are crucial for humoral immunity. They help in the production of antibodies, thus playing a significant role in defending against extracellular pathogens.

Question 9

The major inhibitory cytokine secreted by Treg cells is...&#10;A) IL-1&#946;&#10;B) IL-2&#10;C) IL-6&#10;D) IL-10&#10;E) IL-12

Accepted Answer

IL-10 is the major inhibitory cytokine secreted by Treg cells.

Deck 2: The Human Immune System