*The Immune System Flashcards
*Functions of the Lymphatic System
- Transport excess tissue (interstitial) fluid to the blood stream
- Transport dietary fat
- Help defend the body against disease-causing agents
*How are lymphatic vessels similar to veins?
Have walls similar to veins & possess valves that prevent backflow of lymph.
*What is edema?
- Excessive accumulation of interstitial fluid in tissue spaces
- Obstruction to lymph flow
- Infected lymph node
- Blocked lymphatic vessel
- Increased capillary blood pressure
*Functions of Thymus
- Immature T lymphocytes (T cells) migrate from the bone marrow to the thymus via the blood
- Site of Maturation of T Cells
- The epithelial cells secrete a hormone called Thymosin, which stimulates the maturation of T cells after they leave the thymus & migrate to other tissues.
*Functions of the Spleen
- Removal & destruction of foreign particles & worn blood cells from blood.
- Macrophages remove & destroy bacteria & damagedor worn RBCs & platelets through phagocytosis
- Stores & releases blood during hemorrhage
- In immunity as a site of B cell proliferation into plasma cells
*Total Peripheral Resistance
The total resistance of the flow of blood through the entire cardiovascular system.
What is the relationship between vessel length and TPR?
The longer the vessel the greater the resistance.
What is the relationship between vessel diameter & TPR?
The smaller the vessel, the more resistance.
Which has a greater impact on blood flow? Vessel diameter or length? Why?
Diameter, it causes more friction.
What effect does viscosity have on blood flow?
- The greater the viscosity, the greater the resistance.
- Dehydration causes the blood to become more viscus.
What effect does turbulence have on blood flow?
- The greater the turbuence, the greater the resistance.
- Plaque build up is turbulence
What is Capillary Hydrostatic Pressure?
- Pressure for nutrients to leave capillaries to go into tissues
- Opposite is BCOP (pressure of tissues)
What is filtration?
- When only certain items are allowed to pass through capillaries.
- Not large proteins
- At which region of the capillary does filtration typically occur?
- Where does reabsorption occur?
- What is the relationship between CHP & BCOP at these regions of the capillaries?
- Filtration occurs at the Arteriole side
- Reabsorption at the Venule side
- CHP is filtration, and is higher then; BCOP is reabsorption, and is higher then
What is the difference between central regulation & autoregulation?
Describe some general methods for raising blood pressure when needed.
- Central Regulation: Brain & spinal cord regulate blood flow (Larger vessels, Heart Rate)
- Autoregulation:Organ regulates blood flow by its self
- Raising BP: Make capillaries smaller
What are baroreceptors? Where are they found?
- Pressure Receptors (Monitor BP)
- Found in Aorta & Corotiod Arteries
What events are triggered when baroreceptor detects high BP?
Heart Rate goes down
What events are triggered when baroreceptor detects low BP?
Heart Rate goes up
What are chemoreceptors? Where are they found?
- Monitor Oxygen, Carbon Dioxide, & pH
- Found in Lungs
How does the body handle rising CO2 levels?
Increase in heart rate & bp
How are lymph vessels arranged? What is the arrangement in order from smallest to largest?
- Lymph capillaries
- Afferent vessels
- Efferent vessels
- Lymph Trunks
- Collecting Ducts
Where does the lymph flow back into the bloodstream?
Subclavian Veins
5 Types of WBCs
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
Neutrophils
- Phagocytic
- First Responders
Lymphocytes
- 2 types:
- T: use cytotoxins
- B: use antibodies
Monocytes
Macrophages
Eosinophil
- Allergies
- Parasites
- Eukaryotic pathogens
Basophil
- Inflammation & Allergies
What is the role of lymph nodes?
Hold lymphocytes & filter lymph
What is the flow of lymph through a lymph node?
- Arrive through Afferent Vessels
- Convex Side
- Concave Side
- Exit through Efferent Vessels
- What is the physical barries against infection (the first line of defense)? Be specific.
- What about skin allows it to be a barrier?
- What about oil and sweat allows it to be a defense mechanism?
- Skin, keratin
- Sweat is acidic
- Oil makes it difficult for bacteria to hold on to skin
What WBCs play a role in nonspecific defenses?
- Neutrophils
- Basophils
- Eosinophils
- Monocytes
What is chemotaxis?
WBCs release chemicals into blood stream at sight of infection to attrack more WBCs.
What is diapedesis?
WBC movement through blood vessels to tissues
How do phagocytes destroy bacteria or other foreign microbes?
They eat them (form psuedopods and lysosomes breakdown bacteria)
What is the role of interferons? How do they work? Where do they come from?
- Interfere with viral mechanisms
- Come from infected cells
What is the role of the complement proteins? Know at least 3 mechanisms they use for disabling or destroying foreign microbes?
- 26 of them.
- Group of proteins that work together to fight infection.
- Perferens poke holes in foreign cells
- Antibodies neutralize foreign cells
- Coat bacteria to neutralize them (Opsonisation)
What is inflammation?
Swelling of a tissue (-itis)
What specific type of cell is responsible for triggering the inflammatory response?
Mast Cells (Basophils)
What are the benefits to inflammation? In other words, how does it help you fight infection and allow the body to heal?
- Keeps infection from spreading
- Warm to interfere with function
- Easier for WBCs to come to it
Why make inflammation painful?
So that you will leave it alone.
What is the role of fever? What causes fever?
- Raises body’s temp. to help combat infection & raises heart rate
- Pyrogens
What is the advantage of specific immunity over nonspecific defenses?
Specific goes after a specific antigen which makes them more productive.
What is th difference between innate and acquired immunity?
-
Innate
- Born with it (comes from Mom)
-
Acquired
- By introduction to an antigen
What is the difference between active & passive acquired immunity?
-
Active
- Produce antibodies & differitiate T cells
-
Passive
- Given to you (From Mom)
What is the difference between cell mediated & antibody mediated (humoral) immunity?
-
Cell Mediated
- Use T cells
-
Antibody Mediated
- B cells use antibodies to contain & neutralize
Describe the role of MHC proteins. What is the difference between MHC I & MHC II?
Major Histocompatibility Complex: ID markers
-
MHC I
- Self (Virus CAN alter)
-
MHC II
- Viruses
- Pathogens
- Antigens
Detail what happens to cause a cytotoxic T cell to become active. More specifically, describe what activates it, what it does once it is activated & how it eliminates infected cells.
- T cell encounters an infected cell
- Binds to the infected cell to check its MHC marker and to see if the cell is releasing chemicals that tells that it is an infected cell
- If it is an infected cell, it releases chemicals that causes:
- Apoptosis (Cell Death)
- Interference with the cells metabolism
- Perforines (Poke holes in the cell)
What are the different types of T cells & what are their functions?
-
Helper T cells
- Proliferation of T & B cells
-
Suppressor T cells
- Suppresses immune reaction
-
Memory T cells
- Remain behind incase of a second infection
Describe what happens to a B cell to become active. More specifically, describe what activates it, what it does once it is activated & what role it plays in eliminating foreign microbes.
- B cell enocunters antigen
- Endocytosis of antigen, then displays MHC II marker (Like a Wanted poster).
- B cells proliferate & produce antibodies against specific MHC II.
- B cell turns to plasma cell
What is an antigen? What is an antibody?
-
Antigen
- Triggers an immune response
-
Antibody
- Protein that targets specific antigens. (Made by B cells)
What do antibodies do to help eliminate antigens?
Neutralize them
What is the difference between primary & secondary immune responses?
-
Primary
- First exposure to an antigen
-
Secondary
- Antigen comes again (stronger & quicker)
Describe at least 3 ways (either natural or artificial) in which the human body can acquire immunity against antigens.
- Exposed by natural infection
- Exposed by a vaccine
- Recieve antibodies form mother
What are the five types of antibodie? What specific roles do they have?
-
IgG
- Largest & most diverse antibodies
- Resistance agaisnt many viruses, bacteria, & bacterial toxins.
-
IgE
- Attaches as an individual molecule to the exposed surfaces of basophils & mast cells.
- When bound to a cell, cell releases histamine & other chemicals
-
IgD
- Individual molecule on surface of B cells
- It can bind with antigens in the extracellular fluid
-
IgM
- First class of antibody secreted after an anitgen arrives.
- Forms immune complexes
-
IgA
- Found primarily in glandular secretions
- Attack pathogens before they gain access to internal tissues.
