TRUE OR FALSE (each sentence) 1. t/f Macrophages and dendritic cells can both be antigen-presenting cells.

2. t/f Complement proteins are antibodies produced by skin cells.

3. t/f Dendritic cells are the histamine-producing cells of the immune system.

4. t/f Stomach acid is one of our natural defenses against bacteria in food.

5. t/f Cytokines are molecules that cut holes in bacterial membranes.

6. t/f There are different Toll-Like Receptors for bacteria and viruses.