During the log phase of an immune response, what is happening to the antibody titer?

During the log phase of an immune response, the antibody titer begins to rise significantly. This phase, also known as the exponential phase, is characterized by the rapid proliferation of B cells following exposure to an antigen. These activated B cells differentiate into plasma cells, which are responsible for producing antibodies.

As the immune system responds to the antigen, the concentration of antibodies in the serum increases markedly. This rise in antibody titer is crucial for effectively neutralizing pathogens and marks the body's heightened ability to combat infections. The other phases of the immune response provide context: for instance, prior to the log phase, there is typically a lag phase where the titer is relatively stable, and after the log phase, the antibody levels may peak and eventually decline as the immune response resolves. Thus, the correct choice accurately reflects the dynamic changes occurring in antibody levels during this critical period of an immune response.