Lymphatic System - Mod 4 Flashcards
What are the main components of the lymphatic system?
Lymphatic fluid, lymphatic vessels, lymphatic tissue, and lymphatic organs.
What are the main functions of the lymphatic system?
- Drain excess interstitial fluid from the tissues
- Initiate an immune response against disease by producing and transporting lymphocytes
- Transport dietary lipids absorbed by the gastrointestinal tract into the blood
What is lymph?
A clear fluid similar in composition to blood plasma.
What is the function of lymphatic vessels?
Drain excess fluid from the tissues as lymph and return it into the blood circulation.
What is lymphatic tissue composed of?
Composed of masses of lymphocytes.
What is the general function of the lymphatic organs?
Filter the fluid that flows through the lymphatic vessels, the spleen, thymus, and red bone marrow.
What do lymph nodes contain?
Lymphocytes and macrophages
What is the function of interstitial fluid?
Transports nutrients between blood vessels and cells.
What are lacteals and what do they do?
Lymphatic vessels in the small intestine that transport fats.
What is chyle?
Fat-filled lymph
What are the two main lymphatic ducts and what do they drain into?
The thoracic duct and the right lymphatic duct, they drain into the left and right subclavian veins.
Where does the thoracic duct drain lymph from?
the left side of the body and the lower right side.
Where does the right lymphatic duct drain lymph from?
The right side of the head and thorax and the right arm.
go back to slide 7 and make flashcards if needed.
Where are lymphocytes produced?
In red bone marrow.
What are the primary lymphatic organs?
The bone marrow and thymus.
What are the secondary lymphatic organs?
The spleen, lymph nodes, tonsils, and diffuse lymphatic tissue.
What is produced in the bone marrow, and what do they differentiate into?
Lymphocytes are produced and they differentiate into B pre-T cells.
pre-T cells migrate to the thymus and mature into T-cells.
What is the thymus?
It is a primary lyphatic organ where T-cells mature.
What is the hilum?
It is a slight indentation on one side of the lymph node where an artery, vein, and lymphatic vessel can enter and exit the node.
What is the function of the spleen?
It breaks down and recycles old blood cells and produces white blood cells, which fight infection.
What are the two types of pulp in the spleen and what are their functions?
- Red pulp (blood-filled) - recycles blood cells
- White pulp (lymphoid tissue) - immune functions
What is diffuse lymphatic tissue and where is it found?
Aggregations (clusters) of lymphatic tissue found within the mucosa of the gastrointestinal and respiratory tracts.
What is immunity?
The bodys ability to defend itself against disease and infection.
What are the two types of immunity
Innate imunity and adaptive immunity
What is self-recognition?
The immune systems ability to distinguish between cells of itself and foreign cells, such as bacteria and viruses.
What is innate immunity?
The bodys first and second line of defense against infection, reacting to non-specific pathogens.
What is adaptive immunity?
Memory of past infections that develops over time, enuring more effective future responses.
What is immunological memory?
It’s the ability of adaptive immune cells to remember an antigen and respond faster the next time it appears.
What is the primary immune response?
It’s the body’s first reaction to a new antigen, activating both innate and adaptive immunity.
What two types of cells are made during a primary immune response?
- Active cells: Fight the infection
- Inactive memory cells: Stay in the body and react faster if the same antigen returns later
What is a secondary immune response?
A faster and stronger immune reaction that happens when the body sees the same antigen again.
What are the two lines of defense in innate immunity?
- First line – Physical and chemical barriers like skin and mucous membranes.
- Second line – Internal defenses like phagocytes, NK cells, antimicrobial substances, inflammation, and fever.
What are the two types of protection in the first line of defense?
- Mechanical protection
- Chemical protection
What are natural killer cells and what do they do?
They form part of the second line of defense and are the first lymphocytes to react to infection by destroying infected cells.
What do NK cells release when they bind to an infected cell?
They release granules that contain perforin and granzymes.
What does perforin do?
Creates holes in the plasma membranes of infected cells.
What is cytolysis?
The bursting of cells caused by extracellular fluid flowing into the cell.
What do granzymes do?
They enter the infected cell through the perforin made holes and cause the cell to destroy itself, a process called apoptosis.
