Lymphatic System Flashcards
Lymph
fluid composed of water, electrolytes, cellular waste, and protein
When is lymph formed?
Formed in the plasma during capillary exchange.
Lymphatic vessels
capillaries, larger vessels go to ducts
What are lymphatic vessels called in the abdomen?
lacteals
What does the right lymphatic duct drain?
Right neck and head, right limb, and right side of trunk
What does the thoracic duct drain?
Left neck and head, lower body, left limb, and left side of trunk
What muscles act as a pump and squeeze lymphatic vessels?
Skeletal muscles
What changes cause lymph to flow?
Respiration and pressure changes
What muscles contract in lymph vessels?
Smooth muscles
What causes lymph to flow one way (similar to veins)?
Valves
What filters lymph in the lymphatic system?
Lymph Nodes
What are the three clusters of lymph nodes?
Cervical, axillary, and inguinal
What do cervical lymph nodes do?
Cleanse lymph from the head and the neck
What do axillary lymph nodes do?
Cleanse lymph from the upper extremities, shoulders, and breast
What do inguinal lymph nodes do?
Cleanse lymph from lower extremities and external glands
What type of vessels are going towards the lymph node?
Afferent vessels
What are nodules in a lymph nodes?
Compartments separated by sinuses (lymph-spilled spaces)
What are macrophage cells in nodules?
Defensive cells
How does lymph leave lymph nodes?
Efferent vessels
What are tonsils?
Partially encapsulated lymph nodes in the throat
What do tonsils do?
Filter fluid entering thru the nose and mouth; gather and remove pathogens
What are the three kinds of tonsils?
Pharyngeal, palatine, and lingual
When did the Thymus become active?
Early life
What system does the thymus play a role in the formation of?
Immune system
What happens to the thymus after puberty?
It shrinks
What are thymosins?
hormones promote growth and activity of lymphocytes and lymphoid functions
What is the largest lymphoid organ of the body?
Spleen
Where is the spleen located?
Upper left quadrant
What does the spleen do?
Filters and cleanses blood
What are the two types of tissue found in the spleen?
Red pulp and white pulp
How does blood reach the spleen?
Via the splenic artery
What destroyed microbes in the spleen?
Leukocytes
What blood cells does the spleen destroy?
Old red blood cells
What role does the spleen have before birth?
The formation of red blood cells
How does cleansed blood leave the spleen?
Via the splenic vein
What is localized edema?
Lymphedema
What lymphocytes protect against antigens?
T and B Lymphocytes
How to T cells attack antigens?
They attack directly
How do B cells attack antigens?
They produce antibodies
What kind of cells phagocytize foreign substances?
Macrophage cells
What cells capture antigens and bring them to the lymph nodes?
Dendritic cells
What do reticular cells do in the lymphatic system?
Produce fibrous stroma
What are the primary organs in the lymphatic system?
Red bone marrow and thymus
Where do both T and B lymphocytes originate?
In red bone marrow
Where do T cells mature?
In the thymus
What are the secondary organs in the lymphatic system?
Lymph nodes, spleen, MALT of the tonsils, peyer’s patches of intestine, and appendix
What does MALT mean?
Mucosa-assisted lymphoid tissue
What is the only organ that has afferent vessels?
Lymph nodes
What types of vessels do all of the organs EXCEPT lymph nodes have?
Efferent vessels
What also cleanses the lymph?
Phagocytes
What happens once the lymph nodes activate the immune system?
Dendritic cells bring antigens to the nodes and T cells are activated
How are lymph nodes shaped?
Bean shaped- about 1 inch in length
What is the term for infected lymph nodes (swollen glands)?
Lymphadenopathy
What two structures do lymph nodes have?
Cortex and medulla
What is the internal stroma of a lymph node made of?
Reticular fibers
What are lymph nodes surrounded and divided by?
Surrounded by a capsule, divided by trabeculae
Where do afferent lymphatic vessels lead to?
Sinuses in medulla
Where and how does fluid exit lymph nodes?
Exits at the hilium via efferent lymphatic vessels
What is another action of the spleen?
Lymphocyte proliferation
What two things does the spleen store?
platelets and monocytes
What does MALT include?
the tonsils- palatine, lingual, tubal, and pharyngeal (adenoid)
What are Peyer’s patches?
aggregated lymphoid nodules in the wall of distal small intestine
Where is the appendix?
The beginning of the small intestine
What does the appendix do?
Prevents bacteria from breaching the intestinal wall
Where is the thymus located?
Inferior neck and partially overlies the heart?
