Session 7 - Lymphatic and Immune System 1 Flashcards
Function of lymphatic system
- Drain excess interstitial fluid and large proteins from tissue spaces
- Transporting dietary lipids and vitamins from GI tract to the blood ( Its role in nutrition)
- Facilitate immune responses - recognise microbes or abnormal cells and responding by killing them directly or secreting antibodies that cause their destruction
Excess interstital fluid comes from?
and what happens to it?
At our capillary beds there is a little more filtration than there is absorption and that is the excess interstitial fluid that is then taken up by lymphatic system and returns back to the cardiovascular system.
Lymphatic fluid
similar in compostion to interstitial fluid but some differences in (protein) do occur
Major difference is location
Lymphatic system consists of
- Lymph: the fluid
- Lymphatic vessels: transport the lymph
- Lymphatic organs and tissue: made of specialized form of reticular connective tissue that contains large numbers of lymphocytes
- Red bone marrow: the site of lymphocyte production
Connection of lymph nodes to organs creates
Lymph vessels
Lymphatic capillaries unite to form
Lymph capillaries merge to form larger vessels, called lymphatic vessels, which convey lymph into and out of structures called lymph nodes
Lymphatic Vessles unite to form
lymphatic trunks and thoracic ducts - vessels are similar in structure to veins but are thinner walled and have more valves
Lymph trunks
Lymphatic vessels exit lymph nodes in a particular region of the body, they unite to form lymph trunks
Lymphatic vessels ( supply and exit )
There are lymphatic vessels that supply the lymph nodes and also lymphatic vessels that leave the lymph nodes that unite to form lymph trunks
Lymph ducts
Lymph passes from lymph trunks into two main channels, the thoracic duct and the right lymphatic duct, and then drains into venous blood.
Where are lymphatic capillaries located
Throughout the body along the systemic circulation
- not present in avascular tissue (cartilage, epidermis and cornea), the central nervous system, portions of the spleen, and red bone marrow.
- specialized lymphatic capillaries in the villus of the small intestine, transport digested fats from the small intestine into the blood.
Lymph ducts
Lymph passes from lymph trunks into two main channels, the thoracic duct and the right lymphatic duct, and then drains into venous blood.
- Right side - head, arm and chest empty into right lymphatic duct
- Rest of body empties into thoracic duct
Thoracic ducts drain lymph into venous blood into
left subclavian vein which in turn return it to the circulatory system via the superior vena cava
Right lymphatic duct
Receives lymph from the upper right side of the body
•It drains lymph into venous blood via the right subclavian vein.
sequence of lymph flow
blood capillaries (blood)→interstitial spaces (interstitial fluid) → lymphatic capillaries (lymph)→lymphatic vessels (lymph)→lymphatic ducts (lymph)→junction of the internal jugular and subclavian veins (blood)
What promotes flow of lymphatic fluid
Respiratory and muscular pumps