Question

which of the following defence system components is not considered part of the bodys rst line of defence against infection by pathogens? skin cells helper t cells tears stomach acid

Explanation:

The body's first - line of defence against pathogens includes physical and chemical barriers. Skin cells form a physical barrier, tears contain lysozyme which is an antibacterial substance and stomach acid has a low pH that can kill many pathogens. Helper T cells are part of the adaptive immune system and are not part of the first - line of defence.

Answer:

B. Helper T cells