MCQ IN MEDICINE

Detailed explanation-1: -Thus, the helper T cell activates those B cells with receptors that specifically recognize the antigen that initially activated the T cell, although the T and B cells usually recognize distinct antigenic determinants on the antigen (see Figure 24-70).

Detailed explanation-2: -Helper T-cells have a receptor on their surface called a CD4 receptor. The CD4 receptor interacts with major histocompatibility complex (MHC) class II molecules. MHC class II molecules sense when there’s an infection or foreign substance in your body.

Detailed explanation-3: -Helper T cells become activated through a multistep process, which begins with antigen-presenting cells, such as macrophages. These cells ingest an infectious agent or foreign particle, partially degrade it, and export fragments of it-i.e., antigens-to the cell surface.

Detailed explanation-4: -This is initially compensated for via the production of new helper T cells from the thymus (originally from the bone marrow).