Umme Aimen Tailor - Chapter 12: Lymphology

What are the general functions of the lymphatic system?

1. conduct excess fluid (that filtered out of the cardiovascular system) from the tissues back to the cardiovascular system (vena cava)

2. filtration and phagocytosis of foreign agents

3. production of lymphocytes (WBCs: T-cells, B-cells)

How does lymphatic fluid flow from the capillaries to the heart?

lymphatic capillaries → lymphatic collecting vessels → right lymphatic duct (thoracic) → right subclavian vein (below clavicle)

or

lymphatic capillaries → lymphatic collecting vessels → cisterna chyli →left lymphatic duct → left subclavian vein

What is the right lymph duct?

drains the upper right quadrant of the body

What is the left lymphatic duct?

drains the remaining ¾ of the body

What are lacteals?

lymphatic capillaries in the villi of the small intestine specialized to absorb fat-soluble nutrients from the intestinal tract

What are lymph nodes?

small, round, or bean shaped, organs containing macrophages and lymphocytes (white pulp tissue)

Where is there a large collection of lymph nodes?

cervical, axillary, vertebral, and mesentery (intestines)

What is the spleen?

an organ in the abdomen containing white pulp tissue and red pulp tissue

What is white pulp tissue?

lymphocytes and macrophages

What is red pulp tissue?

large venous sinuses

What are the additional functions of the spleen?

blood reservoir, destruction of worn-out erythrocytes, production of erythrocytes in the fetus only

What is the thymus?

an organ located between the lungs, in the middle of the chest and sternum, atrophies after puberty (shrinks around 12 years old)

What are tonsillar tissue?

1. pharyngeal tonsils (adenoid)

2. palatine tonsils (hard palate)

3. lingual tonsils (tongue)

4. lymphatic nodules of the intestine (peyer’s patches)

5. appendix

What is lymphoedema?

swelling of the lymph nodes, obstruction of lymphatic vessels

What are autoimmune diseases?

disorders of the thymus

what is lupus erythematous?

an autoimmune disease of the skin

What is rheumatoid arthritis?

an autoimmune disease of the joints

What is rheumatic heart disease

an autoimmune disease of the heart

What is myasthenia gravis?

an autoimmune disease of the skeletal muscles

What is multiple sclerosis?

an autoimmune disease of the nervous system

What is ulcerative colitis?

an autoimmune disease of the digestive system

What is juvenile onset diabetes?

an autoimmune disease of the endocrine system