____ 2. The movement of lymph through lymphatic vessels is caused in part by muscular activities of surrounding skeletal muscles.
____ 3. Thymosin promotes the development of all lymphocytes.
____ 4. Lymphocytes initially originate in the red bone marrow.
____ 5. Antibodies are produced and secreted by B cells, once matured into plasma cells.
____ 6. B lymphocytes kill pathogens or foreign cells by direct cell-to-cell contact.
Completion: Complete the following sentences with the correct word or phrase.
7. The main function of the lymphatic system is to transport ______________ back to the bloodstream and to defend against ________________.
8. Lymphatic vessels are more like veins than arteries because they have __________ to prevent backflow.
9. Where does the lymph eventually enter the circulatory system and become part of the blood plasma again? ________________
10. A major function of lymph nodes is the _____________ of lymph.
11. The largest lymphatic organ is the ______________.
12. ______________ barriers against infection include the skin and mucous membranes.
13. Sensitized B cells which do not differentiate into plasma cells remain as _______ cells.
14. ___________ T cells release toxins that destroy antigens directly.
15. Identify the nonspecific body defenses listed below:
______________ Proteins produced from lymphocytes, macrophages, and fibroblasts following infection by a virus..
______________Wandering cells which engulf and digest foreign particles.
______________ Localized tissue response of redness, swelling, heat and pain.
______________ Closely packed epidermal cells makes penetration by pathogens very difficult.
16. A response to a specific pathogen is called ____________.
17. When a person's immune system attacks its own body tissues because it cannot distinguish self from nonself that person has a(n) _______________________ disease.
18. Antibodies are also called ____________________________.
19. __________ are proteins found on the surface of the body cells which allow the immune system to distinguish self from nonself.
20. Tissue rejection may be reduced by _________________ the donor and recipient tissues and by using
_________________ drugs which interfere with the recipient’s immune response.
21. An antigen which stimulates an allergic reaction is called a(n) ________________.