11.  What structural feature of lymphatic vessels is responsible to forward movement of lymph?  
A.  over-lapping endothelial cells
B.  valves
C.  no basement membrane
D.  thin walls

12.  Lymph movement is assisted by  
A.  contraction of skeletal muscle.
B.  contraction of smooth muscle in lymph vessel.
C.  pressure changes in the thorax during respiration.
D.  compression of lymphatic vessels.
E.  All of these choices are correct.

13.  A woman has her right breast and right axillary lymph nodes removed. Which of the following might occur?  
A.  Cisterna chyli flow increases.
B.  The thoracic duct would be severed.
C.  Right lymphatic duct drainage decreases causing edema in the right arm.
D.  Lymph drainage would be affected in her left arm.
E.  Lymph drainage would be affected in both legs.

14.  The right lymphatic duct drains lymph from the  
A.  abdomen.
B.  upper part of the body.
C.  right arm, right chest, and right side of head.
D.  right side of the body.
E.  left arm, left chest, and left side of head.

15.  The thoracic duct drains lymph into the  
A.  left subclavian vein.
B.  right subclavian vein.
C.  right internal jugular vein.
D.  left brachiocephalic vein.
E.  left subclavian artery.

16.  Which of the following organs does NOT contain lymphatic tissue?  
A.  liver
B.  spleen
C.  lingual tonsils
D.  thymus
E.  pharyngeal tonsils.

17.  Lymphatic tissue contains an interlaced network of reticular fibers that functions to  
A.  produce lymphocytes.
B.  produce capsules around lymph nodes.
C.  attack microorganisms.
D.  line the walls of lymphatic vessels.
E.  trap microorganisms.

18.  Nonencapsulated lymphatic tissue called MALT includes all of the following except:  
A.  tonsils.
B.  Peyer patches.
C.  lymph nodes.
D.  diffuse lymphatic tissue.

19.  Peyer patches are lymphatic nodules found in the  
A.  lymph nodes.
B.  spleen and tonsils.
C.  appendix and tonsils.
D.  small intestine and appendix.

20.  Lymph nodules are  
A.  small, bean-shaped structures.
B.  the site of erythrocyte production.
C.  located in the loose connective tissue of the digestive system.
D.  composed of an outer cortex and inner medulla.
E.  connected together in a series.