1. Cytokines are chemical messengers which:

2. The majority of lymph fluid in the body returns to the venous circulation via the

3. Which of the following is an example of naturally acquired active immunity?

4. B-cell lymphocytes mature in the:

5. A role of immunoglobulin G (IgG) is to:

6. Phagocytosis takes place in:

7. The thymus is where T-cell lymphocytes:

8. Lymphoid organs include the

9. One purpose of lymph nodes is to:

10. Which of the following are characteristics of free macrophages and microphages?