THE LYMPHATIC SYSTEM Joe Pistack MS/ED

LYMPH The lymphatic system contains: Lymph Lymphatic vessels Lymphoid organs Lymphoid tissue

Lymphoid tissue is scattered widely throughout the body.

FUNCTIONS OF LYMPH Lymphatic vessels return tissue to the

blood.

Specialized lymphatic vessels play an important role in intestinal absorption of fats and fat soluble vitamins.

Lymphoid tissue helps the body defend itself against disease.

LYMPHATIC SYSTEM Lymphedema-lymph

channels back up and there is a back-up of interstitial fluid.

LYMPH Lymph is a clear fluid that resembles

plasma. Composition:

Water Electrolytes: Na+, Cl. Waste from metabolizing cells. Some albumin that leaks out of the

capillaries.

LYMPHATIC VESSELS Has a similar structure to the blood

capillaries and the veins.

Has the same distribution as the blood capillaries and veins.

LYMPHATIC VESSELS Lymph flows toward the heart through

a series of lymphatic vessels until it reaches the lymphatic ducts.

Lymph from the rest of the body drains into the thoracic duct.

LYMPHATIC SYSTEM

LYMPHATIC VESSELS Both ducts empty the lymph into the

subclavian veins.

Right lymphatic duct drains lymph into the right subclavian vein.

Thoracic duct drains lymph into the left subclavian vein.

LYMPHATIC DUCTS

LYMPHOID ORGANS Includes: Lymph nodes Tonsils Thymus gland Spleen

Lymphoid organs and lymphoid tissue help defend the body against disease.

LYMPH TISSUE

LYMPH NODES Lymph nodes – small pea-shaped

patches of lymphatic tissue strategically located so as to filter the lymph as it flows through the lymphatic vessels.

Lymph nodes tend to appear in clusters.

LYMPH NODES Cervical lymph

nodes: Drain and cleanse

lymph coming from the head and neck areas.

Enlarged tender cervical lymph nodes often accompany upper respiratory infections.

AXILLARY LYMPH NODES Axillary lymph nodes- located in the axillary,

or armpit. Drain and cleanse lymph coming from the upper extremities, shoulder, and breast area.

Cancer cells that escape from the breast are often found in the axillary lymph nodes.

INGUINAL LYMPH NODES Located in the groin

region. Drain and cleanse lymph from the lower extremities and external genetalia.

TONSILS Tonsils-partially encapsulated lymph

nodes in the throat area.

Filter tissue fluid contaminated by pathogens that enter the body through the nose or mouth or both.

Three sets of tonsils.

PALATINE TONSILS Small masses of

lymphoid tissue located at the opening of the oral cavity into the pharynx.

Set of tonsils removed in a tonsillectomy.

PHARYNGEAL TONSILS Also called

adenoids.

Located near the opening of the nasal cavity in the upper pharynx.

Enlargement of the adenoids may interfere with breathing.

LINGUAL TONSILS Located at the back

of the tongue.

THYMUS GLAND Located in the

upper mediastinum in thoracic cavity.

Plays a crucial role in the development of the immune system before birth and in the first few months after birth.

THYMUS GLAND Gland shrinks after puberty but

remains active throughout life

Thymosins- hormone secreted by the thymus gland.

SPLEEN Largest lymphoid

organ in the body.

Located in the upper left quadrant of the abdominal cavity.

Filters blood rather than

lymph.

THE SPLEEN Composed of two types of tissue: (1) white pulp-lymphoid tissue

consisting primarily of lymphocytes surrounding arteries.

(2)-red pulp-contains venous sinus filled with blood and disease-preventing cells such as lymphocytes and macrophages.

RED AND WHITE PULP

FUNCTIONS OF THE SPLEEN Cleansing role Stores blood, especially platelets Destroys and phagocytes, old worn-out

blood cells (called the graveyard of blood cells)

Plays a role in erythropoiesis (site of red blood cell production) before birth

Production of lymphocytes Can live without a spleen, more prone to

infection