QCM : Fundamentals of Immunology — 10 questions

Explication

Lymphocytes are a type of white blood cell that play a central role in adaptive immunity. They include T cells, B cells, and natural killer (NK) cells, each with distinct functions in recognizing and responding to pathogens. This distinguishes them from other immune components such as phagocytes, which are involved in innate immunity, or antigens, which are molecules that trigger immune responses. The development and maturation of immune cells occur in primary lymphoid organs, not lymphocytes themselves.

Explication

Primary lymphoid organs, the bone marrow and thymus, are where lymphocytes mature—B cells mature in the bone marrow, T cells in the thymus. The other options either mention secondary organs or incorrectly describe their functions.

Explication

The complement system was first described in scientific literature in 1890 by researchers who identified plasma components that could lyse bacteria, establishing its role in innate immunity. The other dates are either too early, too late, or not associated with the initial discovery of the complement system.

Explication

Lymphocytes, including B cells and T cells, are essential for adaptive immunity. B cells produce antibodies, while T cells coordinate cellular immune responses. Phagocytes, not lymphocytes, handle pathogen engulfment.

Explication

The primary role of adaptive immunity is to generate a specific and long-lasting immune response against pathogens. It involves lymphocytes such as B cells and T cells that recognize specific antigens, produce targeted responses, and develop memory cells for faster responses upon re-exposure. Unlike innate immunity, which provides immediate but non-specific defense, adaptive immunity is characterized by its specificity and durability.

Explication

Dendritic cells and macrophages are professional APCs that process and present antigens via MHC molecules to T cells, initiating adaptive responses. Red blood cells and platelets do not present antigens.

Explication

Hematopoiesis is the process of producing all blood cells, including immune cells, primarily in the bone marrow. It is essential for maintaining immune system components.

Explication

Immune surveillance refers to the immune system's ongoing activity to detect and eliminate infected or transformed cells, preventing diseases like cancer.

Explication

Lysozyme, found in tears and other secretions, is a chemical barrier that destroys bacterial cell walls, forming part of innate immunity. Skin is a physical barrier.

Explication

Paul Ehrlich, in 1896, significantly contributed to immunology, including concepts of immune specificity and side chain theory. Pasteur and Metchnikoff made other key contributions, but Ehrlich is specifically linked to that publication.