Anatomy Week 8 - Lymphatics Flashcards
(14 cards)
What are the functions of the lymphatic system?
- Main function is to return the lymph from the tissues back into the bloodstream.
- It regulates the balance of fluids in the body and filters the pathogens from the blood.
- Reabsorbs excess interstitial fluid:
- returns it to the venous circulation
- maintain blood volume levels
- Prevent interstitial fluid levels from rising out of control - Transport dietary lipids:
- Transported through lacteals
- drain into larger lymphatic vessels
- eventually into the blood stream - Lymphocyte development and the immune response.
How is lymph returned to the blood?
Lymphatic capillary -> Lymphatic vessel -> Lymph node -> Lymphatic vessel -> Lymphatic trunk -> Collecting duct -> Subclavian vein
Describe Lymph capillaries..
- Blind end
- Single layer of overlapping endothelial cells
- More permeable than that of blood capillary
- Absent from avascular structures, brain, spinal cord splenic pulp and bone marrow
- The small intestine contains special types of lymphatic capillaries called lacteals - absorb dietary lipids and lipid-soluble vitamins
Describe Lymphatic vessels.
- Three layered wall but thinner than veins
- More numerous valves than in vein
- Arranged in superficial and deep locations
Describe the Lymphatic trunk.
- Right and left jugular trunks
- Right and left subclavian trunks
- Right and left broncho-mediastinal trunks
- Intestinal trunk
- Right and left lumbar trunks
Describe Lymphatic ducts.
- Formed by union of right jugular, subclavian, and broncho-mediastinal trunks
- Ends by entering the right venous angle
Describe thoracic ducts.
- At the neck, it turns laterally.
- Arches forwards and descends to enter the left venous angle.
- Before terminate, it receives the left jugular, Subclavian and broncho-mediastinal trunk
What are the primary and secondary lymph organs?
Primary organs:
- Red bone marrow
- Thymus gland
Secondary organs:
- Lymph nodes
- Lymph nodules
- Spleen
Describe Lymph nodes.
- Small, round or oval
- Along the pathways of lymph vessels
- Usually found in clusters, but can be found individually in tissues
- Receive lymph from many body regions
- Has afferent vessels (entering at the periphery) and efferent lymph vessels (emerging at the hilus)
- Divided into superficial and deep
groups
Describe regional drainage.
Occurs through the regional lymph node.
It is the lymph node where the lymph of the organ or part of the drainage to firstly.
Receives lymph from right half of head, neck, thorax, and right upper limb, right lung, thorax and right upper limb, right lung, right side of heart, right surface of liver is lymph drainage from?
Right lymphatic duct.
Drains lymph from lower limbs, pelvic cavity, abdominal cavity, left side of thorax, and left side of the head, neck and upper left limb, is lymph drainage from what?
Thoracic duct.
What type of duct involves the union of right jugular, subclavian, and broncho-mediastinal trunks before it drains to the right subclavian vein?
Right thoracic duct.
What type of duct involves the left jugular, Subclavian and broncho-mediastinal trunk drain into the thoracic duct before the lymph is drained to the right subclavian vein.
Left thoracic duct.
