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Anatomy And Physiology 2 > Lymphatic System > Flashcards

Flashcards in Lymphatic System Deck (30):

What are the three parts of the lymphatic system

Lymphatic vessels, lymph fluid and lymph tissues


What is lymphatic vessels

Network of vessels and capillaries


What is lymph fluid

Fluid in vessels (+ lymphocytes, proteins)


What is lymph tissue

Nodes, spleen, thymus, tonsils and malt


What are the functions of the lymphatic system

Returns leaked fluid to blood vessels, defence of bodies


Describe the lymphatic vessels

One way flow of fluid, vessels have valves. Lymph flows toward heart. Vessels merge to form thoracic duct which empties into vena cava


Describe lymph formation

Plasma, interstital fluid, lymph


Describe the lymphatic capillaries

Microscopic blind ended, highly permeable: picks up pathogens and cancerous cells as well as plasma proteins: role of lymph nodes. Mini valves which open when interstitial osmotic pressure is greater than lymphatic. Blind ended tubes in which adjacent endothelial cells overlap each other forming flap like minivalves.


What are lacteals

SpecialiZed lymph capillaries present in intestinal mucosa - absorb digested fat and deliver fatty lymph (chyle) to the blood


What are lymphoid tissues

Place for lymphocytes (B+T cells) to live and patrol for pathogen. Composed mainly of loosely connective tissues ( reticular connective tissues ).


How is lymphoid tissue dispersed

In organs. Diffused or found in clusters (nodules). Peyers patches in wall of ileum.


What are large nodules

Lymph nodes


What are lymph nodes

Principal lymphoid organs of body, in clusters along the lymphatic vessels.


What are the defence functions of lymph nodes

Filter lymph - macrophages destroy pathogens and prevent them from entering blood.
Activate immune system: B cells and T cells lymphocytes attack pathogens or infected cells


Describe the spleen

Largest lymphoid organ, also has a hematologic function


What is the function of the spleen

Site of some clonal selection + antibody production in immune response. Rbc graveyard - destroys old red blood cells and platelets, macrophages remove debris.
Stores blood


Is the spleen essential for life

Nope, other organs can take over function in event of splenectomy


What is the thymus

Found in cervical region. Partially overlies heart and trachea. Important functions early in life (neonate). Gradually atrophies and replaced by fatty fibrous tissues


What is the thymus the site of

Site of T-Cell maturation
Contains no B cells


What are tonsils

Differ from lymph nodes: no fibrous capsule surrounding them. Found in moist epithelial mucosal surfaces not a long lymph vessels in middle of body.
Gather and remove pathogens in food (digestive tract) or air (respiratory tracts). Mainly found in pharynx


What is malt

Lymphoid tissue in mucous membranes throughout body. Protects from pathogens trying to enter body. Large collections of malt in tonsils, peyers patches. Also in mucosa of respiratory and genitourinary organs: rest of digestive tract - galt


What is neoplasia

Abnormal growth of tissue


What is lymphoma

Cancer of lymphatic tissue types: B cell/T cell proliferation: multicentric: lymph nodes, spleen, liver, bone marrow
Mediastinal: thoracic structures
Extranodal: skin, eyes


What are the symptoms of lymphoma

Enlarged lymph nodes, lethargy, depression, and weight loss, fever, vomiting, diarrhea


What is cbc abnormal symptoms:

Anemia, lymphocytosis


What are abnormal fna symptoms:

biopsy: lymphocytosis


What is fiv: feline immunodeficiency virus

Virus that targets lymphocytes and macrophages causing lymphopenia: progressive. Most often transmitted through bites: vertical transmitted is less common.


How do you test for fiv and how do you treat it

Test for antibodies: vaccinated cats may test positive. Negative cats may have not yet produced antibodies. No cure : time of death: 5 yrs after infection


What is felv:

Also caused by retrovirus. More easily transmitted than FIV: mainly through saliva and nasal secretions, urine feces and milk. Progressive disease. Causes leukaemia, lymphomas, and suppression of immune systems


Is there a vaccination for felv

Vaccine available but not beneficial if infected. Test for antigens