Human anatomy exam 3 Chapter 22 Flashcards
(30 cards)
What does the lymphatic system do?
- Returns fluids that have leaked from the circulatory system back to the blood
- Protects by removing foreign material
- Protects by providing a site for immune surveillance
What are the components of the lymphatic system?
The lymphatic vessels and capillaries
What do lymphatic vessels do?
- travel and associated w/ blood vessels
- not found in bones teeth bone marrow and the CNS
What do lymphatic capillaries consist of?
- microscopic blind (ended tubes)
- Lacteals which are specialized lymph capillaries of the intestinal mucousa
Where can fatty lymph be found? and what are they?
- can be found in the lacteals of the capillaries of the lymphatic system
- it is chime that contains fats and fat soluble material absorbed in the lacteals
Is the lymphatic vessel permeable and how come?
- it is permeable
- permeable because of the presence of endothelial cells not tightly joined
what are the anatomical features of the lymphatic vessel?
4
- permeable
- forms mini valves
- has collagen filaments to anchor to surrounding structure
- proteins and large particles are able to enter lymph vessels
how do the mini valves work for the lymphatic vessel?
if fluid pressure in interstitial is greater than pressure in lymph capillary then the valves open and fluid enters the vessel
what occurs if the fluid pressure interstially is less then the pressure of the lymph capillary?
the mini valves within the lymphatic vessel would not open
how does the lympatic system transport materials
- through a circulation a low pressure system
- valves,respiratory pumps and muscular pumps to move lymph towards the heart
- uses capillaries
what duct receives lymph from the rest of the body
the thoracic duct
what are the lymphoid cells of the body?
- Lymphocytes
- T Cells
- B Lymphocytes
- Macrophages
- Dendritic Cells
- Reticular cells
What does the lymphatic tissue do?
- provides a site for proliferations and houses the lymphocytes
- primarily composes of reticular CT
- Diffuses lymphatic tissue
- the lymphoid follicals also contain the dendritic cells and B cells
What are the lymphoid organs?
- lymph nodes
- spleen
- thymus
- Tonsils
- Clumps of Lymphoid follicals
- Malt (mucousa associated lymphatic tissue)
What does the lymphatic organ known as the lymph nodes do and found?
- filter lymph w lymphatic vessels
- embedded in connective tissue
- Found in inguinal,axillary and cervical regions
State the pathway of lymph entering and exiting the nodes?
- lymph enters node through the AFFERENT lymphatic vessels
- lymph exits the node through the EFFERENT lymphatic vessels
What is the largest lymphoid organ
The spleen
What does the spleen do in the lymphatic system?
- cleanses body by removing old RBC/ platelets
- Stores break products of RBC’s
- Site of erythropoiesis in fetus
What does the thymus organ do for the lymphatic system?
- the site of T cell maturation
- Lacks B cells and no reticular fibers are present
The lymphoid organ known as the tonsils have 3 different pairs and are 6 in total what are they?
- Paletine tonsils
- Lingual Tonsil
- Land pharyngeal tonsils
what do the clumps of lymphoid follicles do?
- destroy bacteria and prevent pathogens from slipping through intestinal walls
- they generate memory lymphocytes as well (long term immunity)
Where can MALT(mucosa associated with the lymphatic tissues be found)?
- tonsils
- peyers patches
- appendix
- follicles found in bronchi
What are the first line of defense for the immune system?
- skin (keratine and epidermis)
- mucousa such as mucus nasal hair and cilia, tear saliva and gastric juices
What is the second line of defense of the immune system?
- phagocytes include (macrophage, neutrophils, mast cells, and eiosinophils)
- Natural killer cells
- antimicrobial proteins (interferons)
- inflammatory response
