Question

Which of these cells help activate B cells? a) Helper T cells b) Cytotoxic T cells c) Macrophages d)
Neutrophils
23. Which of these is a second line of defense? a) Skin b) Stomach acid c) Inflammation d) Hair
24. Which of these is NOT part of the immune system? a) Spleen b) Bone marrow c) Heart d) Lymph
nodes
25. Which of these is an example of passive immunity? a) Vaccination b) Breast milk antibodies c)
Infection recovery d) None
26. Which of these cells remember past infections? a) Memory cells b) Plasma cells c) Macrophages d)
Neutrophils
27. Which of these is a role of the spleen? a) Produce antibodies b) Filter blood c) Make antigens d)
None

Answer 1

22. a) Helper T cells — they activate B cells (and help coordinate immune responses).
23. c) Inflammation — an internal (second-line) innate defense.
24. c) Heart — not part of the immune system.
25. b) Breast milk antibodies — transfer of antibodies is passive immunity.
26. a) Memory cells — they retain memory of past infections.
27. b) Filter blood — the spleen filters blood and helps remove old red cells and pathogens.