Module 12 : The Lymphatic System Flashcards
1
Q
the lymphatic system
A
- drainage system that returns extracellular fluid to the body circulation
- three types of extracellular fluid
+ plasma
+ interstitial
+ lymph
2
Q
plasma
A
- colorless fluid in the blood that seeps through capillary walls
3
Q
interstitial fluid
A
- plasma that has seeped through capillary walls and circulates among body tissue
4
Q
lymph
A
- interstitial fluid that drains out of the tissue and enters the lymphatic ducts
5
Q
lymphatic anatomy
A
- similar to circulatory system but different because
+ lack a pump
+ travel in one direction
+ contains lymph nodes - consists of capillaries vessels ducts and nodes
- course along circulatory system
6
Q
capillaries
A
- blind ended structures in interstitial spaces, single endothelial layer
- join together to form larger vessels
- valves to control direction of flow
- superficial drain into deep lymph
- deep vessels pass through nodes on their way towards chest
- in chest blood reenters blood stream
7
Q
lymph nodes
A
- important component of RE system
- distributed throughout body
- bean shaped accumulations o lymph tissue scattered along the lymphatic vessels
- measure from 1mm to 1-2 cm
- surrounded by connective tissue capsule
8
Q
afferent vessels
A
- drain into node
- carry lymph through the sinuses (lined with phagocytic cells)
+ filter out and destroy bacteria and malignant cells
9
Q
germinal centers
A
- sponge like centres in the node
- produce lymphocytes
- empty into lymph prior to leaving the node
10
Q
efferent vessel
A
- leave only at hilum
11
Q
lymph node and disease
A
- rarely seen as the primary site of disease
- secondary disease may be seen as result of spread
12
Q
two major node bearing areas in retro peritoneum
A
- iliac and hypogastric = pelvis
- para aortic = upper retroperitoneum
+ lymph chain follows the course of the thoracic aorta, abdominal aorta and iliac arteries
13
Q
other lymph tissue
A
- tonsils
- thymus
- spleen
14
Q
lymphatic circulation
A
- deep and superficial drainage
- groups of nodes at key locations
+ axillary
+ cervical
+ inguinal
+ intestinal (peyers patch) - right lymphatic duct drain into right upper quadrant
- left lymphatic duct (thoracic duct) drains remaining 3/4 of the body
15
Q
lymph - physiology
A
- extracellular fluid formation
- similar to blood plasma - higher albumin (maintain blood volume) ratio
- low leukocyte count
- no RBCs
- digestive enzymes
