26 - Physiology of the lymphatic system. Formation, composition and functions of lymph. Physiology of the spleen.

section

physiology of lympathtic system

formation, composition and function of lymph

lymph composition

function of lymph

physiology of spleen

physiology of lympathtic system

• network of tissues and organs that help the body remove toxins and other unwanted material.

• The primary function is to transport lymph, a fluid rich in WBC, throughout the body.

• lymph organs-

  • spleen tonsils

  • bone marrow

  • thymus

  • lymph nodes - where lymph is filtered connected by lymph vessels.

• The thymus is the central organ of the lymphatic system.

• Lymphatic tissue contain infection fighting cells

formation lymph

1. Blood capillaries push fluid (plasma minus large proteins) into tissues due to pressure—this becomes interstitial fluid.

2. Most of this fluid returns to capillaries; about 10% stays in the tissue.

3. This leftover fluid enters lymphatic capillaries through special one-way valves.

4. Once inside lymph vessels, the fluid is called lymph.

lymph composition

contains proteins, salts, water, electrolytes, fats, glucose and WBC

function of lymph

1. Removal of interstitial fluid from tissues

2. It absorbs and transports fatty acids and fats as chyle from the (small intestine) digestive system

3. It transports WBC to and from the lymph nodes into the bones

4. The lymph transports antigen-presenting cells (APCs), such as dendritic cells, to the lymph nodes where an immune response is stimulated.

physiology of spleen

• Is not a vital organ- not essential for life

• filters and stores blood to protect the body from infections and blood loss.

• Function:

  • Blood reservoir, prevent blood loss during injury

  • helping to fight infections thanks to the reservoir of lymph nodules with B, T-lymphocytes as well as free and fixed macrophages

  • involved in the recycling of old red blood cells