Chapter 16 Flashcards
What modifications help in the movment of lymph?
- The squeezing action of skeletal muscles aids movement.
- The low pressure in the thoracic cavity created by breathing movements, moves lymph up from abdominal to thoracic region.
- one-way valves also help in the movement of lymph
What is inflammation?
- Is a tissue response to damage, injury or infection.
- Blood vessels dilate, increasing capillary permeability.
What are some characteristics of the IgD immunoglobulins?
- Occurs on the surface of most B-cells
- Involved in activation of B-cells.
Define Artificially acquired active immunity
A person who receives a vaccine containing a dead or weakened pathogen.
What is an allergic reaction?
Is an excessive inflamatory response against a non-harmful substance
Discuss the flow of lympg through the lymph nodes
- Lymph flow is in one direction.
- Lympatic capillaries
- Lymph enters the node through an afferent lymphatic vessel.
- Flows inward through sinuses
- Exits the node via an efferent lymphatic vessel at the hilum.
- Goes to the lymphatic trunk
- Collecting ducks
- Right and Left subclavian veins
What may cause autoimmune disorders?
- Previous viral infection.
- Faulty T-cell development.
- Reaction to a non-self antigen that is close in structure to a self-antigen.
- Persistent fetal cells, where fetal cells persist in the female’s circulation as an adult.
What are Natural Killer Cells?
- A group of lymphocytes that defend against viruses and cancer cells by secreting perforins.
- Perforins are compounds that lyse the cell membrane.
What is the thymus and its role in the lymphatic system?
- Thymocytes can be converted to T-lymphocytes and leave the thymus.
- Hassall’s corpuscles secrete thymosins which stimulate maturation of the T-lymphocytes after they leave the thymus.
What is adaptive resistance?
Protection against particular pathogens or to their toxins or metabolic by-products (specific target).
What are the 4 classes of immunity?
- Naturally acquired active immunity
- Artificially acquired active immunity
- Artificially acquired passive immunity
- Naturally acquired passive immunity
What is phagocytosis?
The process by which cells engulf and ingest foreign particles in order to destroy them.
Phagocytic cells are present at the spleen, liver, bone marrow and blood vessels.
What are some characteristics of the IgG immunoglobulins?
- IgG – occurs in plasma and tissue fluids.
- Most prevalent of the IGs.
- Defends against bacterial cells, viruses and toxins.
- Activates complement.
- ***Only antibody to cross placenta
What are autoimmune disorders?
When the the body produces antibodies against “self”-antigens, resulting in an attack on one’s tissues.
Define: Artificially acquired passive immunity
A person who receives an injection of gamma globulin that contains read-made antibodies.
Provides short-term production.
What are the six different mechanisms of nonspecific resistance?
- Species resistance
- Mechanical barriers
- Chemical barriers
- Fever
- Inflammation
- Phagocytosis
aWhat are the 5 major types of immunoglobuins?
- IgA
- IgD
- IgE
- IgG
- IgM
What are lymphatic nodules?
- Nodules are aggregated into a solitary, oval-shaped mass.
- Commonly found at the small intestine (Peyer’s patch and tonsils).
Define Immediate-reaction allergy
- Causes the production of an abnormally large amount of IgE.
- The response occurs within minutes of contact with the allergen.
What are some characteristics of the IgE immunoglobulins?
- Occurs in exocrine gland secretions.
- Promotes inflammation and allergic reactions due to the release of histamine from mast cells (basophils).
What is thymosin?
A substance that stimulates the maturation of the T-lymphocytes after they leave the thymus.
Define primary organs.
These are sites where cells are produced that carry out an immune response.
Define naturally acquired active immunity
when an individual encounters a live pathogen, which stimulates a primary IR, and suffers symptoms of a disease.
How are B-cells activated?
- B-cells become activated when they bind to an activated T-cell.
- Activated B-cells then proliferate, enlarging its clone.
- Activated B-cells develop into plasma cells that secrete antibodies.