Lymphatic System
What is immunological tolerance?
A state of unresponsiveness for a particular antigen
All of the following are true of the thymus gland, except _______________
A) activates B cells. <--- EXCEPT THIS B) reaches its greatest relative size during the second year of life. C) involutes after puberty. D) produces T cells. E) lies in the anterior mediastinum.
Physical barrier to infection includes _________________
A) sebaceous glands. B) mucus. C) epithelia. D) epidermal layers.
Where are Lymphocytes found?
A) tonsils B) spleen C) lymph nodes D) thymus **All of them
The cells responsible for humoral immunity are the ________ cells.
B cells
What is the function of Vermiform appendix?
"worm-like" inferior to cecum of large intestine immune functions function: destroys intestinal bacteria and produces lymphocytes
What is MALT? What role does it play in the body's defenses?
-MALT is an acronym for Mucosa Associated Lymphatic Tissue. -It consists of aggregated aggregated lymphatic nodules deep to the mucosa (gut lining) of the digestive system. -Examples include Peyer patches in the small intestine and the vermiform appendix that is attached where the small intestine joins the large intestine. -These lymphocytes are positioned to detect and neutralize pathogens to enter the body across the digestive mucosa. ---Beside these specific defenses, there is also mucus and other protective secretions.
What is the function of the lymphoid (lymphatic) system?
-Return lymph that leaked into capillaries into right ventrical -Transports fat from digestive tract to the blood -Produce lymphocytes -develop immunity
What are Peyer patches?
-Wall of small intestines; like tonsils -work with the immune system to protect against the entry of pathogens through the digestive systems -contain macrophages that destroy bacteria
What is immunodeficiency disease?
Conditions resulting from defective immune mechanisms
What is the function of NK cells?
Kill cells that are infected with intracellular parasites. Kill cells that have ben genetically transformed. and Secrete interferon-y
Know different components of the lymphatic system.
Lymph, Lymph Vessels, Lymph Nodes, Tonsils, Spleen, Thymus Gland, Peyer's Patches
Examples of physical barriers against pathogens include ______________________________
Lymphocytes
What is opsonization?
The coating of an antigen or particle (eg, infectious agent) by substances, such as antibodies, complement components, fibronectin, and so forth, that facilitate uptake of the foreign particle into a phagocytic cell.
What are interferons?
They are secreted from infected cells; cause surrounding cells to produce a substance that prevents viral replication
Know how Lymphoid organs differ from lymphoid tissues?
They are surrounded by a fibrous capsule and lymphatic tissues are not.
Where do the T cells mature?
Thymus
What is an autoimmune disorder?
When the individual develops antibodies of their own cells. These antibodies attach to self antigens & begin attacking the individual's tissues.Inflammation as well as tissue necrosis occurs. Autoimmune disorders can be general or systemic.
Know the two areas of spleen - white pulp and red pulp.
White pulp- Specialized lymphatic tissue within the spleen that contains many lymphocytes Red pulp- Specialized lymphatic tissue within the spleen that contains red blood cells, macrophages, & lymphocytes.
What are immunoglobulins?
any agent capable of inducing an immune response by T and/or B lymphocytes all immunogens are antigens, but not all antigens are immunogens( not all antigens are capable of producing an immune response)
Compare to blood capillaries to lymph capillaries
blood capillaries converge to form venules and then veins lymphatic capillaries unite to form larger lymphatic vessels which resemble veins in structure but have thinner walls and more valves. lymphatic vessels in the subcutaneous tissue generally follow route of veins. lymphatic vessels of the viscera follow route of arteries. lymphatic vessels close at one end causing only a one way path for lymph to flow.
Stem cells that will form B cells or NK cells are found only in the _________________
bone marrow.
Newborns gain their immunity initially from _____________________________
contact with siblings. breast milk. antibodies passed across the placenta from the mother. contact with viruses and bacteria. early immunizations.
Lymphocytes that destroy foreign cells or virus-infected cells are ________ cells.
cytotoxic T
The cells directly responsible for cellular immunity are the ________ cells.
cytotoxic T
T cells and B cells can be activated only by ________________________________
exposure to a specific antigen at a specific site in a plasma membrane.
What are antigens?
generate an immune response; an antibody generator
Cells that help regulate the immune response are ________ cells.
helper T
The human immunodeficiency virus (HIV) that causes the disease known as AIDS selectively infects ________ cells.
helper T
Immunity that is genetically determined and present at birth is called ________ immunity.
innate immunity
What is the function of Peyer's patches?
located on the walls of the small intestine; work with the immune system to protect against the entry of pathogens through the digestive systems
Chronic or excessive enlargement of lymph nodes is __________________
lymphadenopathy
An inflammatory response is triggered when _____________________________
mast cells release histamine and heparin.
Immunity that results from exposure to an antigen in the environment is called ________ immunity.
naturally acquired active immunity
The first line of cellular defense against pathogens are the ___________________
phagocytes.
The cells responsible for the production of circulating immunoglobulins are ________ cells.
plasma
Leslie has a bad sore throat and the lymph glands in her neck are swollen. This would indicate that _____
the affected lymph nodes contain an increased number of lymphocytes.
Stem cells that will form T cells develop in the __________________________________
thymus.
In a routine examination, some blood is taken and analyzed. The results show a high IgM titer for the mumps virus but a low IgG anti-mumps titer. This would indicate the person ______________
was recently infected with mumps.
What is delayed hypersensitivity?
Hypersensitivity reaction that takes place 48-72 hours after exposure to antigen; mediated by T cells and macrophages
During a primary immune response, the ______________________
IgM titer is initially higher than the IgG titer.
The largest single collection of lymphoid tissue in the adult body is located in the what?
Spleen
What is cisterna chyli?
Enlarged terminus of the thoracic duct that receives lymph from the digestive viscera.
What are tonsils?
Multiple aggregations of large lymphatic nodules embedded in a mucous membrane. ex. pharyngeal (adenoid), palatine, and lingual tonsils
Know the difference between specific and non specific defenses.
Specific- Specific immunity are things that protect the body from specific pathogens. It includes the third line of defense. They include the lymphocytes (white blood cells) such as the macrophages, t cells, and memory b cells. Non-specific- nonspecific immunity are things that protect the body from various bacteria, viruses, and pathogens. These include the first and second line of defense, such as the skin, fever( body gets hot as an attempt to kill the pathogen).
