Health Science Technology Dr. Halbert Lymphatic System Health Science Technology Dr. Halbert

Objectives Understand the flow of lymph through the lymph vessels List the functions of lymph nodes Identify the 2 lymphatic ducts and the areas of the body that each drain List the functions of the spleen Describe the function of the thymus Understand the disease of the lymphatic system Define the vocabulary words

Vocabulary Words Cisterna chyli Lacteals Lymph Lymph nodes Lymphatic capillaries Lymphatic system Lymphatic vessels Right lymphatic duct Spleen Thoracic duct Thymus Tonsils

Lymphatic system Consists of lymph, lymph vessels, lymph nodes and lymphatic tissue

Lymph Thin watery fluid composed of interstitial fluid, digested nutrients, salts, hormones, O2, CO2, lymphocytes, metabolic waste

Lymphatic vessels Located throughout the body in almost all the tissues that have blood vessels Contain valves

Lymphatic capillaries Small open ended lymph vessels Pick up lymph (about 3 L a day) at tissues throughout the body

Lymphatic capillaries join together to form larger lymphatic vessels, which pass through lymph nodes Contraction of skeletal muscle causes the lymph to flow Lymphatic vessels have valves that keep flow in one direction

Lacteals Specialized lymphatic capillaries in the area of the small intestine pick up digested fats or lipids Chyle: lymph mixed with lipids

Lymph nodes “glands” Located throughout the body, usually in groups

Functions of lymph nodes Filter lymph and remove impurities such as carbon, cancer cells, pathogens, dead blood cells Produce lymphocytes and antibodies (substances used to combat infection)

Lymphatic vessels leaving the lymph nodes join together to form larger lymph vessels and these vessel drain into one of two lymphatic ducts: right lymphatic duct or the thoracic duct

Right Lymphatic Duct Receives purified lymph from the right side of the head, neck and chest and the right arm Empties into the right subclavian vein

Thoracic Duct Larger and drains lymph from the rest of the body Empties in to the left subclavian vein

Cisterna chyli Pouch like structure at the start of the thoracic duct Serves as a storage area for purified lymph

Examples of Lymphatic Tissue Tonsils Spleen Thymus

Tonsils Three pairs: Palatine tonsils: on each side of the soft palate Pharyngeal tonsils (adenoids): in nasopharynx Lingual tonsils: back of the tongue

Spleen Located beneath the left side of the diaphragm and in the back of the upper part of the stomach

Functions of the Spleen Produces leukocytes & antibodies Destroys old erythrocytes Stores erythrocytes Destroys thrombocytes Filters metabolites & wastes

Thymus Located at the center of the upper chest Atrophies after puberty Produces antibodies & fights infection in early life

Diseases of the Lymphatic System

Adenitis Inflammation of the lymph nodes

Hodgkin’s disease Chronic malignant disease of the lymph nodes Most common form of lymphoma

Lymphangitis Inflammation of the lymphatic vessels, usually resulting from infection in an arm or leg

Splenomegaly Enlargement of the spleen May occur from: Abnormal accumulation of RBCs Mononucleosis Cirrhosis

Tonsillitis Inflammation of the tonsils, usually the pharyngeal & palatine tonsils

Image Citations Slide 4, 6, 7, 10, 22: Delmar Learning’s Medical Terminology Image Library, Second Edition, Version 1.0, 2003. Slide 15: The Thoracic Duct, 3/17/06, http://www.med.uottawa.ca/medweb/demo_site/undergrad/webct/lectures/curriculum_hn/e_hn1_crs_lec06.htm Slide 17: Lymph vessels and nodes of the small intestines, 3/17/06, http://www.med.uottawa.ca/medweb/demo_site/undergrad/webct/lectures/curriculum_hn/e_hn1_crs_lec06.htm Slide 19: Tonsils, 3/17/06, http://www.med.uottawa.ca/medweb/demo_site/undergrad/webct/lectures/curriculum_hn/e_hn1_crs_lec06.htm Slide 20: Spleen, 3/17/06, http://www.shands.org/health/surgeries/100040.html Slide 24: Tuberculosis Adenitis, 3/17/06, http://www.thachers.org/internal_medicine.htm Slide 25: Hodgkin’s Lymphoma, 3/17/06, http://www.surgical-tutor.org.uk/default-home.htm?system/vascular/hodgkins.htm~right Slide 26: Hand Infection with Ascending Lymphangitis, http://www.davidlnelson.md/Infection1_ascending_lymph.htm Slide 27: Splenomegaly, 3/17/06, http://www.humc.net/humc_ency/images/ency/fullsize/17212.jpg Slide 28: Tonsillitis, 3/17/06, http://www.altcancer.com/tonsillitis.htm