The Japanese word for Japan is æ¥æ¬, which is pronounced Nippon or Nihon and literally means the origin of the sun. The earliest record of the name Nihon appears in the Chinese historical records of the Tang dynasty, the Old Book of Tang.
The secondary immune response occurs the second time (3rd, 4th, etc.) the person is exposed to the same antigen. At this point immunological memory has been established and the immune system can start making antibodies immediately.
For second and subsequent encounters with similar antigens, secondary (anamnestic) immune responses occur. Here, the lag phase is shorter, and high and steady levels of antibodies are generated within a few days. This is due to antigen-specific memory T and B cells, originally produced during the primary response.