Sample Biology Essays On Clonal Expansion Theory

Homework Question on Clonal Expansion Theory

  1. Describe how the clonal expansion theory explains the more rapid production of antigen specific antibodies, Helper T-cells and Cytotoxic T-cells, during a secondary infection.
  2. Compare and contrast how a farmer would use Rhizobium versus Bacillus thuringiensis? Are there any other types of microbes the farmer could use for similar purposes?

Homework Answer onClonal Expansion Theory


In the clonal expansion theory, antigens serve as templates for the creation of the antibodies. Antibodies are proteins, which are involved in destroying infectious agents. Antigens react in progressions on the surface of antibodies that are involved in the production of cells. The body already possesses antibodies that are made in specialized cells, which it requires in fighting infections (Taylor, 2012). The kind of interaction that occurs between antigens and antibodies led to expansion of plasma cells (B-cells) and T-cells.

When antigens are linked with the receptors, the clonal expansion occurs in the cells. Helper T-cells play a key function in the immune system while Cytotoxic T-cells are directly involved in killing cells. The process of forming antibodies involves a random procedure. T-cells maintain their cycle even after the infection is over. Effective immune response is demonstrated during secondary infection when a large number of B-cells are identified rapidly, leading to quick response due to the presence of receptors.

Homework Help


Farmers have been utilizing Rhizobium, natural bacteria, to fix nitrogen in the soil by turning it into a form that is easily absorbed by plants. Rhizobium works with numerous leguminous plants, such as beans, groundnuts, as well as soybeans. On the other hand, Bacillus thuringiensis is a bioinsecticide that occurs naturally in the soil.