Lymph and lymph vessels Flashcards
What are the primary functions of the lymphatic system?
Transport and house lymphocytes and other immune cells
Return excess fluid in body tissues to blood to maintain blood volume
What are the main components of the lymphatic system?
Lymph vessels, lymphoid tissues and organs
What is lymph?
The fluid transported within lymph vessels
What are the characteristics of lymph?
Some fluid leaves blood capillaries and is not reabsorbed by them
This interstitial fluid moves into lymphatic capillaries where it is then called lymph
What are the components of lymph?
Water, dissolved solutes, small amount of protein
Sometimes cell debris, pathogens, or cancer cells
What are lymphatic capillaries?
Small, closed-ended vessels that absorb interstitial fluid
How do lymphatic capillaries compare in size to blood capillaries?
Slightly larger than blood capillaries; no basement membrane
What is the structure of lymphatic capillary walls?
Made of overlapping endothelial cells
Have flaps between cells through which fluid enters but can’t exit
What role do anchoring filaments play in lymphatic capillaries?
Hold endothelial cells to nearby structures
What are lacteals?
Lymphatic capillaries in GI tract that absorb lipid-soluble substances from GI tract
How does lymph move into lymphatic capillaries?
Hydrostatic pressure of interstitial fluid pushes it into capillary
Pressure of lymph inside vessel forces intercellular openings of capillary wall to close with lymph inside
What is the progression of lymph movement through the lymphatic system?
Lymphatic capillaries, lymphatic vessels, lymphatic trunks, and lymphatic ducts
What happens to lymph ultimately?
Fluid is returned to blood circulation
True or False: Wandering cancerous cells can establish secondary tumors in other locations in the body.
True
What is metastasis in the context of cancer?
Development of secondary tumors in other locations in the body
How can cancerous cells spread from a primary tumor?
They break free from the primary tumor and are transported in the lymph
Fill in the blank: Lymphatic capillaries absorb _______.
[interstitial fluid]
Fill in the blank: Lymph is composed of water, dissolved solutes, and a small amount of _______.
[protein]
