The proliferation of the B lymphocyte to which a specific antigen binds is referred to as __________.

• A. an activation sequence
• B. a cascade mechanism
• C. antigenic variation
• D. an autoimmune response
• E. clonal selection

Answer: (E)

Verified step by step guidance

1. Understand the role of B lymphocytes in the immune system: B lymphocytes, or B cells, are a type of white blood cell that plays a crucial role in the adaptive immune response by producing antibodies.
2. Learn about the concept of clonal selection: Clonal selection is a process where a specific B cell is selected for proliferation because it has receptors that bind to a specific antigen. This process ensures that the immune system can respond effectively to pathogens.
3. Recognize the importance of antigen binding: When an antigen binds to a B cell receptor, it triggers the B cell to proliferate and differentiate into plasma cells and memory cells, which are essential for producing antibodies and providing long-term immunity.
4. Differentiate clonal selection from other immune processes: Clonal selection is distinct from other processes such as antigenic variation (changes in antigens to evade the immune system) and autoimmune responses (where the immune system attacks the body's own cells).
5. Conclude that the proliferation of B lymphocytes upon antigen binding is best described by the term 'clonal selection', as it specifically refers to the selection and expansion of B cells with receptors for a particular antigen.