Lymphatic System (Questions - EXAM #2) Flashcards
What does the lymphatic system consist of?
The lymphatic system consists of lymphatic vessels, lymph nodes, and lymphoid cells, tissues, and organs.
What is the primary function of the lymphatic system?
It collects and returns approximately 10% of extracellular fluid (lymph) from tissues to the venous blood, helping to cleanse it and support immune function.
What do lymph nodes do in the lymphatic system?
Lymph nodes filter lymph as it passes through, removing bacteria, viruses, and cancer cells.
What is the difference between intracellular and extracellular fluid?
Intracellular fluid is found within cells (~40% of body weight), while extracellular fluid is outside cells and includes blood plasma (~5% body weight), interstitial fluid (ISF, ~15%), and lymph (~1%).
What is interstitial fluid (ISF)?
ISF is the fluid between cells, and some of it moves into lymphatic capillaries to become lymph.
What is lymph?
Lymph is the fluid inside lymphatic vessels, derived from ISF, and is eventually returned to the blood plasma.
How does lymph move through the lymphatic system?
Lymph enters lymphatic capillaries, moves through larger collecting vessels, and is filtered by lymph nodes. It then drains into either the right lymphatic duct or the thoracic duct.
What is the function of one-way valves in the lymphatic vessels?
They ensure that lymph flows in one direction and prevents backflow.
What does the right lymphatic duct drain?
The right lymphatic duct drains lymph from the right side of the head, chest, and arm, and empties into the right subclavian vein.
What does the thoracic duct drain?
The thoracic duct drains lymph from the left side of the body and below the ribs, and empties into the left subclavian vein.
Where does the thoracic duct start?
The thoracic duct begins at the cisterna chyli, an enlarged portion of the vessel that collects lymph from below the ribs.
What is the role of lymphoid tissues and organs?
They contain lymphocytes and play a key role in the body’s immune response.
What are primary lymphoid organs?
Primary lymphoid organs are where lymphoid stem cells divide and mature. These include red bone marrow and the thymus gland.
Where do B lymphocytes proliferate and mature?
B lymphocytes proliferate and mature in the red bone marrow.
Where do T lymphocytes proliferate and mature?
T lymphocytes proliferate and mature in the thymus gland.