(a)[2]
Define gene.
(b)[4]
Outline how antibodies help defend the body against pathogens.
(c)[4]
Complete Table 2.1 by giving the structure name and the letter that identifies it. The first row has already been completed for you.
(d)[2]
State the name of one cell type, other than a lymphocyte, that contributes to body defence against pathogens and describe its role.