Lymphatics Flashcards
What are the components of the lymphatic and immune system
-lymph
-lymphatic vessels
-organs
-red bone marrow
What is lymph
-lymph is blood plasma that filters out of capillaries
What is the difference between lymph and interstitial fluid
-if the blood plasma is found in lymph vessels it is called lymph, if the blood plasma is found in between cells it is called interstitial fluid
How is lymph formed
-from the interstitial fluid, as it enters the lymph vessels
What are the major functions of the lymphatic and immune system
- drains excess interstitial fluid
- transports dietary lipids
- carriers out immune response
What is the function of T- cells
-also known as T lymphocytes, they are found in large numbers in lymph nodes
-function to attack viruses, fungi, bacteria, cancer cells, transplanted cells, and cause allergic and rejection reactions
What is the function of B-cells
-also known as B lymphocytes, found in large numbers in the lymph nodes
-function to destroy bacteria and toxins
What are lymphatic capillaries
-vessels found in spaces between cells
-closed at the terminal end
-unite to form lymphatic vessels
-subcutaneous vessels follow a similar pattern as veins
-viscera lymph vessels follow similar routes as arteries and form plexuses
-avascular tissues lack lymph vessels
What causes fluid to enter the lymphatic capillary, and what prevents it from leaking back out
-interstitial pressure causes cells in lymphatic capillaries to separate and allow fluid in but fluid cannot leave
How does edema affect the passage of fluid into the lymphatic capillary
-more interstitial pressure which opens a path further for more fluid to enter lymph capillary
What is a lacteal
-lymphatic capillaries in the small intestines that take in dietary lipids and transports them to the blood
Are there any tissues that lack lymphatic capillaries
-avascular
-cartilage
-epidermis
-cornea
-CNS
-parts of the spleen
-red bone marrow
Describe the relationship between lymphatic capillaries, lymphatic vessels, lymph nodes, and lymphatic ducts
Lymph flows –> lymphatic capillaries –> lymph vessels –> lymph nodes –> lymphatic trunks –> thoracic duct (left) and right lymphatic duct –> blood at the junctions of the left and right internal jugular veins and subclavian veins
Name two main lymphatic ducts, what does each do?
Thoracic duct: drains the left side of the head, neck, chest, left upper limb, and entire body inferior to the ribs
right lymphatic duct: drains the upper right side of the body
Where do each of the main lymphatic ducts drain lymph into the circulatory system
-each duct drains lymph at the junction of the internal jugular and subclavian veins on the right and left
What forces help lymph move through the lymphatic system
-the same forces that return venous blood to the heart and maintain lymph flow
1. skeletal muscular pump: muscle contractions compress lymph vessels
2. respiratory pump: during inhalations, lymph flows from higher pressure in the abdomen to lower pressure in the chest and valves prevent backflow during exhale
What is the function of the primary lymphatic organ, and what are the primary lymphatic organs in the adult body?
-organs are sites where cells become immunocompetent
-they are red bone marrow and thymus
What is the function of the secondary lymphatic organ, name the secondary lymphatic organs in the adult body.
-site of the immune response
-lymph nodes and spleen
Describe the location of the thymus
-in the mediastinum between the sternum and aorta
-al the white dots in the picture are T cells
-the clear areas are thymic corpuscles that stain lighter and fewer T-lymph
-have swirls of keratinized epithelial cells
-corpuscles prevention of autoimmune response
What is the function of the thymus
-develops/matures T cells to become immunocompetent, has its own barrier
How does the thymus change as the human or other type of mammal ages
-active tissues atrophy and are replaced with fat
Where are the lymph nodes located and what is their function
-scattered in groups
-mammary glands, axillae, and groin have large clusters of nodes
–filter lymph and houses B and T cells that destroy foreign substances as lymph filter through
What is the function of the afferent and the efferent lymphatic vessels
afferent = carry lymph to nodes
efferent = carry lymph away from nodes
location of the spleen
-found on the left side of the abdominal cavity between the diaphragm and stomach
Name two kinds (colors) of tissue found in the spleen
-red pulp
-white pulp
What is the function of the white pulp
-white pulp contains lymphocytes and macrophages to destroy blood-borne pathogens
What is the function of the red pulp
-red pulp contains filled sinuses with RBC, macrophages, lymphocytes, plasma cells, and granulocytes
-function is to remove macrophages, RBC and platelets that are no longer useful, platelet storage, and fetal RBC production
What are tonsils
-tonsils are lymph nodules in the nasal cavity, nasopharynx, oral cavity, and oropharynx
-they trap ingested/inhaled substances into crypts where B cells and T cells attack and destroy
