X Her brotherâs illness forced her to explore feelings that had lied dormant for some time. â â¦. that had lain dormantâ¦ [past perfect of lie (1)]. X I laid down on my bed and went to sleep. â I lay down on my bedâ¦ [simple past of lie (1)]. X Sheâs laying flat on her back, out for the count. â Sheâs lying flat on her backâ¦ [present continuous of lie (1)]. X When she died, she was lain in an ornate wooden coffin. â â¦she was laid in an ornate wooden coffin.
The receptors match only one specific antigen. White blood cells called lymphocytes originate in the bone marrow but migrate to parts of the lymphatic system such as the lymph nodes, spleen, and thymus. There are two main types of lymphatic cells, T cells and B cells.he receptors match only one specific antigen. White blood cells called lymphocytes originate in the bone marrow but migrate to parts of the lymphatic system such as the lymph nodes, spleen, and thymus. There are two main types of lymphatic cells, T cells and B cells.
Helper T cells activate B cells that produce antibodies. Supressor T cells slow down and stop the immune response of B and T cells, serving as an off switch for the immune system. Cytotoxic (or killer) T cells destroy body cells infected with a virus or bacteria.mmunity results from the production of antibodies specific to a given antigen (antibody-generators, located on the surface of an invader). Antibodies bind to the antigens on invaders and kill or inactivate them in several ways. Most antibodies are themselves proteins or are a mix of protein and polysaccharides.