Lymphatic Structures
Lymphatic Vessels (Lymphatics)
Network of vessels that begin peripherally and collect in venous system vessels
Lymph
Fluid similar to plasma that flows through lymphatic vessels
Lymphocytes
specialized cells responsible for defending the body
The three major types of lymphocyte are T cells, B cells and natural killer (NK) cells.
Lymphoid Tissues / Lymphoid Nodules
Lymphoid Organs
Functions of the Lymphatic System
Pathogen
virus, bacteria, fungi, parasite
can be found in human body and are responsible for disease
Pathogen/Antigen/Allergen
Immunity
Body’s ability to resist or activate defenses to eliminate the pathogen
Lymphatic Vessels
Lymph vessels are a compliment to the cardiovascular system
At the begining of the Arteriole-Caplilary-Venulole Network
Begining of Capillary network
Hydrostatic pressure exceedes Osmotic pressure causing Loss of fluid out of the capillary into ECF
@ End of Capillary network
Osmotic pressure exceeds Hydrostatic pressure causing some fluid to be regained, but there is still a net loss into the Extracellular fluid.
Net loss contributes to the ECF, which inturn is sucked up into the lymphatic vessels.
Lymphatic vessels are one way transport, with ducts to prevent back flow.
Fluid is brought back centraly and dumped into subclavian veins which return fluid to SVC and systemic circulation.
*Single layer of simple squameous epithelium, important because it allows fluid to diffuse easily from the ECF into the Lymphatic Vessel

Lymphedema
A side effect of the removal of lymphnodes
Often seen with removal of axillary lympnodes in efforts to stop the metastasis of breast cancer.
Due to the loss of lymphnodes, edema presents in adjacent arm.
Thoracic Duct
&
Right Lymphatic Duct
White Blood Cells
5 Types
Lymphocytes
Thymus


T-Cells
Thymus Dependent Cells
account for 80% of all Lymphocytes
Three Types:
B-Cells
Bone Marrow Derived Cells
account for 10-15% of all Lymphocytes
Antibody
Antigen
Antibody and Antigens
Antibody
Antigen
NK Cells
Natural Killer Cells
account for 5-10% of all lymphocytes
Lymphopoesis
is the synthesis and development of lymphocytes
Lymphoid Tissues / Lymphoid Nodules
Lymphoid Organs
Lymphnodes


Spleen

