21.2 True/False Questions
1) Lymph is propelled through the lymph vessels by the force of the heartbeat.
2) If lymphatic vessels are surgically removed, the resulting edema is permanent because these vessels cannot regenerate.
3) Lymph capillaries are open-ended like drinking straws.
4) Epithelial cells within the thymus secrete hormones that are important to lymphocyte development.
5) The right lymphatic duct drains the intestinal trunk.
6) Lacteals are the micro-valves present in lymph collecting vessels.
7) The thymus increases in mass through childhood and then atrophies during adulthood.
8) Lymphangitis is inflammation of a lymphatic vessel.
9) The spleen atrophies during adulthood.
10) Lymph capillaries are absent from the central nervous system.
11) Lymph transports fats absorbed from the small intestine to the vena cava.
12) Deep lymphatic collecting vessels of the abdominal cavity travel alongside deep arteries.
13) The thymus is the only lymphatic organ that does not directly fight antigens.
14) To activate lymphocytes, bacteria must penetrate the epithelium of tonsils.
15) Vaccination mimics acquired immunity.