The Lymphatic System Flashcards
What are the 3 anatomic components of the lymphatic system?
- lymph fluid
- lymphatic vessels
- organized lymphatic tissue
What is the physiologic function of the lymphatic system?
Homeostatic mechanisms: immune, digestive, fluid balance, waste
Describe the embryological timeline of the lymphatics system
formed in the 5th week and is significantly present by the 20th week
The _______ contributes to the lymphatic vessels, lymph nodes, spleen, and myeloid tissue
mesoderm
the ______ contributes to the thymus and parts of the tonsils
endoderm
Describe the timeline of the lymphoid tissue throughout the life
Immature at birth
Increases at 6-9 years
At puberty, the system matures but regresses until 15-16
remains stable throughout the rest of the life
Describe fluid balance
30 L of fluid moves from the capillaries to the interstitial space everyday
90% to capillaries and 10% to lymphatic system
The lymph system will help with fluid overload
What is the function of the lymph fluid?
Bathes the organs and cleanses the extracellular space of toxins
fluid travels from vessel to node and acts as a purifier
How is the lymphatic system able to contribute to the defense of the body?
lymph fluid delivers everything to the lymph nodes which have high concentrations of immune cells
How does the lymph system contribute too digestion?
Helps to absorb the fats via chylomicrons because they are too big to cross the intercellular junctions
Describe the components of lymph fluid. How do they get there?
substances that leak out of the arteries into the interstitium that are taken up by the lymph
contains…
immune cells, antigens, bacteria and viruses, clotting factors, and chylomicrons
What are tissues that do NOT have lymphatic vessels?
Epidermis
Endomysium of muscle
Cartilage
Bone marrow
Describe the flow of the lymphatics
terminal lymphatics collecting vessels afferent lymph vessels lymph nodes efferent lymph nodes lymphatic trunks thoracic duct or right lymphatic duct venous system
Describe terminal lymphatics
lymph formation begins in the interstitial space of tissues
lined by leaky endothelium and anchored by small filaments
they gather into the collecting vessels
_________ are chains of muscular units that possess two-leaflet bicuspid valves referred to as “lymphatic hearts”
Lymphangions
What is the function of lymph nodes?
Filtration of lymph fluid
Maturation of lymphocytes
Phagocytosis of bacteria and cellular debris
What is the path of the lymph fluid in the lymph node (basic)
- Afferent lymph
- sub capsular space
- outer cortex
- deep cortex
- medullary sinus
- Efferent lymphatics
What are the lymphatic regions?
- lumbar
- intestinal
- bronchmediastinal
- subclavian
- jugular
The ______ ______ is located at the level of L1-L2 and drains the lymphatic trunks of the lower body, giving rise to the thoracic duct
cisterna chyli