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.
In this first encounter, there are only a few cellsthat can mount an immune response and the response isrelatively weak. This is called a primary immune re-sponse (figure 57.18).If the primary immune response involves B cells, somebecome plasma cells that secrete antibodies, and some be-come memory cells.