Chapter 14: Lymphatic system and immunity Flashcards
List the 3 functions of the lymphatic system
- Returns fluid and solutes from the peripheral tissues to the blood, and keeps interstitial fluid consistent throughout the body
- Produce, maintain, and distribute Lymphocytes
- Distribute Hormones nutrients, and waste products from their tissues of origin to the general circulation
what is Lymph
LIQUID
it’s like plasma in blood, but with fewer protiens
what is in the lymphatic system?
Lymph
lymphatic vessels
lymphocytes
lymphatic tissues and organs
what are primary lymphoid tissues and organs?
Where lymphocytes are made
- red bone marrow
- thymus
What are secondary lymphoid tissues and organs?
where lymphocytes are activated and mass produced
- spleen
- appendix
- Lymph nodes
- tonsils
- Malt
What is Malt
AKA Mucosa-associated lymphoid tissue
- mucus(ish) that is found in and protects the epithelium of the digestive, respiratory, urinary, and reproductive tracts.
how are lymphatic capillaries different from CV capillaries?
CV capillaries leak fluid OUT
- The simple squamous epithelium of lymphatic capillaries has an overlap that acts as a one-way valve.
- Fluid and solutes and leak INTO a lymphatic capillary, but can’t get back out
- CV=2 way
- L=one way
List the 4 pressures that case CV capillaries to leak
1- Hydrostatic pressure on the capillary pushing blood out of the capillary
2- osmotic pressure pulling blood into the capillary
3- Hydrostatic pressure on the interstitial fluid pushing it into CV and L capillaries
4- osmotic pressure pulling blood into the interstitial fluid
what is the difference between lymph and interstitial fluid?
Interstitial Fluid:
- is the extra cellular fluid surrounding tissues.
- Composition standard across the whole body
Lymph:
- transport fluid
- moves fluid, solutes, and waste products out of lymph and to the circulation
- home of lymphocytes
Name 2 types of lymphoctyes
B cells
T cells
Natural killers
What are B cells
- Made in bone marrow
- differentiate into plasma cells
- the antibody factories
What are T cells
- Made in the thymus
- most of the circulating lymphocytes
What are cytotoxic T cells
directly attack foreign cells or virus infected cells
what are Hepler T cells
stimulate the activities of B cells and T cells
Suppressor T cells
inhibit B cells and T cells`
What are Natural Killer cells
Help with nonspecific immunity
- monitor peripheral tissue cells for anything wrong with them
what is innate immunity?
- don’t look for anything in particular
- prevent/limit the spread of microorganisms or other environmental hazards
- predetermined at birth (does not need to exposure to anything)
what is Adaptive (specific) immunity
- T cells and B cells target specific antigens
- not present at birth
- exposure to antigen required
- B cells and T cells make special memory cells that remain targeted to the antigen and can rapidly propagate to quickly fight off any return of the problem antigen.
what are 2 types of specific immunity
Active: Exposure to antigens cause antibody development
Passive: antibodies given to you from an outside source
What is natural immunity
- Doctors not involved
- environment leads to immunity
Natural Active: develops after exposure to the environment
Natural passive: mother pass to children through placenta and breast milk
What is induced (acquired) immunity
Doctors stimulate immunity
- Artificially induced active: Develops after administration of an antigen to prevent disease. This is the principle behind vaccination.
Artificially induced passive: Antibodies are administered to combat infection
types of innate immunity
- physical barriers( skin or mucous)
- Phagocytes
- immune surveillance with natural killer cells
- interferons: protein that tell target cells to make antiviral proteins to inhibit viral replication
- Complement system
- inflammation
- fever
how does the completment system produce resistance to diseas
set of proteins that works with antibodies to isolate pathogens, signal phagocytes to eat the target, destroy the plasma membrane of the target, and promote inflammation.
how does inflammation produce resistance to disease
Caused by anything that kills cells or damages loose connective tissue, it causes tissue repair to start, slows pathogens moving away from the injury, and recruits a bunch of defenses to the area to do more repair and kill pathogens. Mast cells are key players here.
how does fever produce resistance to disease
Circulating proteins can tell the hypothalamus to crank up the temperature. Many viruses and bacteria are very temperature-sensitive, so this slows them down or kills them.
Albumin
plasma protein
- most common
- creates osmotic pressure
immunoglobulins
AKA antibodies
- plasma protein
- bind to pathogens and other foreign materials
Trasport globulin
- plasma protein
- binds to things such as small ions and hormones that need to be carried to their destination
Fibrinogen
plasma protein
- is needed for clotting
- it gets activated to from fibrin when clotting occurs
- fibrin is the frame work for a clot
IgG
Type of Gamma Globulins
- most of the antibodies
- responsible for defense against viruses, bacteria, and toxins
IgM
Type of Gamma Globulins
- first antibody made in response to initial exposure to an antigen
- catch bad things that are missed by IgG
IgA
Type of Gamma Globulins
- Antibodies found in glandular secretions and attack pathogens before they can get to the body tissues
IgE
Type of Gamma Globulins
- bound to mast cells and basophils
- bind to antigen and release histamine and heparin to call for WBC
IgD
Type of Gamma Globulins
- on the surface of B cells
- May help in the sensitization of B cells
What is primary antibody response?
- antigen has to activate correct B cells that respond my differentiating into plasma cells (this takes a while)
- plasma cells are antibody factories
- Some B cells become memory B cells and don’t become plasma cells until SECOND exposure
what is secondary antibody response
- 2nd exposure to antigen tells memory B cells to differentiate into plasma cells
-A lot faster than Primary
A lot stronger than primary
-Memory B cells live a long time, so the secondary response can be vigorous decades after an initial exposure.
how do autoimmune diseases develop?
Sometimes, an autoantibody slips through the tolerance checks, so you naturally make an antibody against self (autoantibody). This is the problem in type 1 diabetes and rheumatoid arthritis.
- A few pathogenic antigens look enough like self proteins (especially in the myelin sheath) that the antibodies to those antigens also hit self proteins, causing autoimmune diseases such as myasthenia gravis.
