0 the cells and tissues in the body that make it able to protect itself against infection --
1 the body's cells and organs that fight illness and disease --
Similarly, the immune system has its own effector system of antibodies and immune cells to carry out the immune reaction.
The immune system is thus a highly adaptive organ, changing in response to the requirements of the organism at large.
In this context the placenta is not an effective barrier between one component of the maternal immune system and the fetus.
The vertebrate immune system usually succeeds in recognising and eliminating foreign materials, causing little or no damage to host tissues.
The immune system discriminates between transformed cells and normal cells by virtue of the presence of unique antigens on tumour cells.
A two-pronged approach, aimed at developing vaccines to overcome the defects of the ageing immune system and designing age-specific vaccination strategies, is of extreme priority.
We picked gene-based selection in biology, the immune system, and operant learning because we thought that they were the least problematic examples of selection.
Genes play very different roles in operant behavior and the immune system.
