1. Lymphatic System

2. Introduction Components: Functions: Lymph fluid Lymphatic vessels
Lymph nodes and organs
Functions:
Drains excess interstitial fluid – return this fluid to the blood stream
Transport fats from the digestive tract to the bloodstream
Immune responses

3. The Lymphatic System FG23_01.JPG Title: Lymphatic System
Notes: An overview of the arrangement of lymphatic vessels, lymph nodes, and lymphoid organs.
Keywords: lymphatic system, components, lymph nodes, cervical, axillary, pelvic, inguinal, lumbar, right lymphatic duct, thoracic lymphatic duct, mammary gland, spleen, gut-associated, cisterna chyli, thymus, lymphatics of lower limb

4. Lymphatics Originate as lymph capillaries
Allow fluid to enter but not exit through one way valves
Capillaries unite to form larger vessels
Resemble veins in structure
Connect to lymph nodes at various intervals
Lymphatics ultimately deliver lymph into 2 main channels
Right lymphatic duct
Drains right side of head & neck, right arm, right thorax
Empties into the right subclavian vein
Thoracic duct
Drains the rest of the body
Empties into the left subclavian vein

5. Lymph Capillaries

6. Lymphatic Vessels

7. Main Channels of Lymphatics
FG23_04.JPG
Title: Lymphatic Ducts and Lymphatic Drainage
Notes: The thoracic duct collects lymph from tissues inferior to the diaphragm and from the left side of the upper body. The right lymphatic duct drains the right half of the body superior to the diaphragm.
Keywords: lymphatic ducts, circulatory system, jugular trunk, thoracic lymphatic duct, subclavian trunk, thoracic lymph nodes, intestinal trunk, cisterna chyli, azygos vein, right lymphatic duct

8. Lymph Nodes Oval structures located along lymphatics
Enclosed by a fibrous capsule
Lymph enters nodes through afferent lymphatics, flows through sinuses, exits through efferent lymphatic
Contain high concentrations of immune system cells (white blood cells)
Memory immune cells detect foreign molecules and are activated

9. Lymph Node

10. Immune responses
Upon encountering a foreign molecules memory cells are activated and create an immune response
The immune response involves cells not bound to the lymph nodes which then replicate and move throughout the body via the lymphatic/cardiovascular systems.

11. Tonsils Multiple groups of large lymphatic nodules
Location – mucous membrane of the oral and pharyngeal cavities
Palatine tonsils
Posterior-lateral walls of the oropharynx
Pharyngeal tonsil
Posterior wall of nasopharynx
Lingual tonsils
Base of tongue

12. Tonsils

13. Spleen Largest lymphatic organ Located between the stomach & diaphragm
Many of the same functions as lymph nodes
Located between the stomach & diaphragm
Additional functions
Removes worn out/defective/ruptured red blood cells (RBC)
Storage of platelets
Production of new RBC

14. Spleen FG23_17B.JPG Title: The Spleen
Notes: (a) The shape of the spleen roughly conforms to the shapes of adjacent organs; transverse section. (b)Visceral surface of intact spleen; major anatomical landmarks. (c)Histological appearance of the spleen.
Keywords: spleen, transverse, abdominopelvic cavity, kidneys, pancreas, hilus, diaphragm, gastrosplenic ligament, stomach, liver, rib, white pulp, visceral surface, gastric area, splenic vein, splenic artery, renal area, histology, trabecular arteries, capsule, red pulp

15. Thymus Gland Located behind the sternum
The capsule divides it into 2 lobes
Function
Differentiation and maturation of one type of lymphocytes (type of white blood cells)

16. Thymus Gland FG23_16A.JPG Title: The Thymus
Notes: (a)Location of thymus on gross dissection. (b)Anatomical landmarks on thymus. (c)Low-power light micrograph of thymus. (d)Higher magnification showing structure of Hassall's corpuscles.
Keywords: thymus, gross dissection, thyroid, trachea, lobe, septae, lobule, cortex, medulla, blood vessels, Hassall's corpuscles, epithelial cells, lymphocytes

17. Autoimmune diseases Autoimmune – self immunity
Immune cells start to recognize your own cells as being foreign molecules.
Can result in a number of different diseases depending on what is now considered to be foreign

18. Autoimmune diseases Type I diabetes (juvenile diabetes)
Beta cells which produce insulin are targeted as foreign and destroyed by the immune system.
Little to no insulin is produced
This prevents uptake of glucose (sugar) by tissues
Glucose is our main source of energy.

19. Rheumatoid Arthritis Pain swelling and stiffness in the joints
Typically in the fingers and wrists
Can affect other parts of the body such as eyes and lungs
Exact cause is unknown

20. Sarcoidosis Commonly referred to in the TV show House, not sure why.
Inflammation of the lungs, skin or lymph nodes

21. Narcolepsy Recent studies suggest this may be an autoimmune disease
Uncontrolled sleep cycles
May last a few seconds to several minutes long.