Circulatory System: Lymphatic and Immunity Flashcards
Functions of the lymphatic system
- Drainage of interstitial fluid
- Transport of lipids (from digestive system)
- Protection and immune responses
Structures of the Lymphatic System
- Lymph (fluid of the system)
- Lymphatic Vessels (transport fluid)
- Structure and organs that contain lymph tissue
- Red bone marrow (BCs develop)
What is lymph?
It is the excess filtered fluid of plasma and solutes
Where does lymph come from?
From blood from the capillaries, into the interstitial space–> then drains into lymphatic system
How do proteins that leak out of the blood return to circulation?
Via the lymphatics
What are the steps of lymphatic flow?
Capillaries–> Lymphatic Vessels–> Trunks –> Ducts
Structure of Lymphatic Capillaries
- Begin in the spaces between cells
- Closed at one end
- High permeability
How is fluid allowed into the capillaries and not out?
Endothelium overlap, pressure drives interstitial fluid in
Lymphatic capillaries merge into ____
Larger vessels called lymphatic vessels
What do lymphatic vessels to help move lymph along?
One way valves (little smooth muscle component)
At regular intervals, lymph passes through ___
Lymph nodes
Structure of Lymph Nodes
- Clusters of lymphocytes (B cells/T cells), surrounded by a dense CT capsule
- Bean shaped
Function of Lymph Nodes
Lymph Filtration
Lymph flows in, foreign substances trapped and destroyed
Larger Lymphatic Vessels merge into ___
Trunks
What are the two lymphatic ducts?
- Thoracic Duct
2. Right Lymphatic Duct
What does the thoracic duct drain and where?
-Left side of the head/neck
-Left side of the body
-Entire body below ribs
Drains into Left Subclavian Vein
What doest the right lymphatic duct drain and where?
-Right side of head/neck
-Right side of chest
Drains into Right Subclavian Vein
Lymphatic Flow:
- Blood Capillaries (Blood)
- Interstitial Space (Interstitial Fluid)
- Lymphatic Capillaries (Lymph)
- Lymphatic Vessels (Lymph)
- Lymphatic Ducts (Lymph)
- Subclavian Veins (Blood)
What is Lymphatic Flow maintained by?
- Skeletal Muscle Pump
- Diaphragmatic Breathing/Respiratory Pump
- Smooth Muscle Contraction (minimal)
Lymphatic Organs
- Red Marrow
- Thymus
- Spleen
Produces B cells and immature T cells
Red Marrow
Produce mature T cells from pre-T cells
Thymus
Where is the thymus located?
Mediastinum
How is the thymus at birth, what happens to it as we age?
Large, atrophies with maturity
Filters blood, removes ruptured, worn out, defective RBCs and stores platelets and monocytes
Spleen