Chapter 15

Lecture 4, Pgs. 461-468

Lymphatic system

Many additional substances, including fluid and protein molecules, that cannot enter or return through the capillary walls are returned to the blood as lymph

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Lymph

Specialized fluid formed in the tissue spaces that is transported by lymphatic vessels to re-enter the circulatory system

Lymph

The lymph is drained into the subclavian veins through the right lymphatic duct and the thoracic duct

* See figure 15-3, page 4633/4 of the body drains through the thoracic duct, which is the largest lymphatic vessel in the body

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Lymph

The lymph system also includes the lymph nodes, thymus & spleen

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Lymph nodes

Lymph goes through nodes as it works its way back to the veins

They are located in clusters along the pathway of lymph vessels

* See figure 15-1, page 462

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Lymph nodes

Functions:1. White blood cell formation2. Filtration (defense)

Lymph nodes

Lymph nodes will swell during bouts with infectionExamples: swollen “glands” in the neck or throat area, armpit, or groin areas, or others

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Lymph nodes

Doctors will examine nodes for presence of cancer cellsIf found it probably metastasized

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Thymus

Small lymph tissue located in the mediastinumImportant in the formation of T cellsT cells help in immunityHIV infects and destroys T cells

Person has little immunity

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Tonsils

Lymph tissue in the mouth & back of the throat; form protective ring around internal opening of nose & throatHelp protect against bacteria that may invade tissues in that area

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Tonsils

Palatine- each side of throat* See figure 15-8, page 468Pharyngeal- near back of nasal cavity (also known as adenoids)

Lingual- near base of tongue

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Tonsils

May be chronically infected and have to be removed if they do not respond to antibioticsTonsillitis- inflammation of the tonsils

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Spleen

Largest lymph tissue located high in the upper left quadrant just lateral to the stomach

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Spleen

Has a very rich blood supply (up to one pint)

Filters, destroys old RBC’s, salvages iron to be used later, holds blood so it can be returned to the bloodstream if needed

Spleen

It can be injured by trauma, especially if it is swollen or enlarged (protected some by ribs)It will enlarge (splenomegaly) during some diseases, like mono, scarlet fever, syphilis, typhoid fever

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Spleen

If injured, it may be life threatening because of internal bleedingSevere pain in the abdomen, pain down left armSpleen may have to be removed (splenectomy) to stop loss of blood

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.