• Single, unpaired organ located in the mediastinum
• Extends upward to the lower edge of the thyroid
• Extends inferiorly as far as the 4th costal cartilage

• Located near the posterior opening of the nasal cavity.
• AKA adenoids

• Refers to a tumor of the cells of lymphoid tissue.
• Often malignant and in rare cases benign.

• Lymphedema can be caused by small parasitic worms called filaria.
• Infest the lymph vessels.
• They are mainly seen in the tropics.

• An acute inflammation of the lymphatic vessels, stems from invasion of an infection of an organism.
• Characterized by thin, red streaks extending from an infected region up the arm or leg.

• Lymphatic vessels

How much lymph from the breast enters the nodes of the axillary region?

And where does the remainder of lymph enter the nodes?

85%

Along the lateral edges of the sternum.

• Clear, watery fluid found in lymphatic vessels
• Closely resembles blood plasma in composition but has a lower percentage of protein.

Referring to the general circulation rate of lymph and how it is maintained.

How does lymph move through the system?

• In the right direction because of the large number of valves.
• Breathing movements and skeletal muscle contractions establish a fluid pressure gradient, as with venous blood.
• Lymph flows through the thoracic duct and reenters the general circulation at the rate of 3 liters a day.

• Complex, organized fluid that fills the spaces between the cells and is part of the ECM.
• Resembles blood plasma in composition with a lower percentage of protein.

What happens to the thymus in advanced old age?

• Oval-shaped enclosed by fibrous capsule
• May range in size from 1mm to more than 20mm in diameter.

1. Defense-macrophages lining the sinusoids of the spleen remove microorganisms from the blood and phagocytose them.
2. Hematopoiesis-monocytes and lymphocytes complete their development in the spleen.
3. Red blood cell and platelet destruction-macrophages remove worn-out RBCs and imperfect platelets and destroy them phagocytosis; also salvage iron and globin from destroyed RBCs
4. Blood reservoir-pulp of spleen and its sinuses store blood

Too wordy??  Probably knowing the functions of the spleen would be sufficient :)

2 most important:

1. Maintain fluid balance in the internal environment
2. Immunity

Third function is to collect absorbed fat from the intestines and transport it to the systemic veins.

Upper right quadrant

Right lymphatic duct

Right subclavian Vein

Thoracic duct

left sublavian vein

cisterna chyli.

few millimeters

more frequently in smaller lymphatics

Name the groups of lymph nodes with greatest clinical importance:

(7 of them)

1. Submental
2. Submaxillary
3. Superficial cervical
4. Superficial cubital
5. Axillary
6. Iliac
7. Inguinal lymph nodes

Reticuloendothelial cells remove microorganisms and other injurious particles from lymph and phagocytose them (biological filtration).

(If overwhelmed, lymph nodes can become infected or damaged)

1. Lymphatics that drain the skin over the breast with the exception of the areola and nipple.
2. Lymphatics that drain the underlying substance of the breast, as well as the skin of the areola and nipple.