AP 2 Quiz lecture Lymphatic

Lymphatic system

principal body system that helps defend against disease-causing illness

Pathogens

diseases producing microbes

Immunity

the body’s ability to ward off damage or disease through natural defense

Susceptibility

the body’s lack of resistance or vulnerability to the pathogen

Pathogen, microbe, foreign invader, antigen, disease causing agent =

things that enter the body that the body identifies as not supposed to be there – attack + kill

Nonspecific resistance (innate immunity)

present at birth and includes defense mechanisms that provide general protection against invasion by a wide range of pathogens

Immunity (Adaptive Immunity)

involves activation of specific lymphocytes that combat a particular pathogen or other foreign substance

Lymphocyte

immune specific cells

The lymphatic system consists of

several structures and organs that contain lymphatic tissue, bone marrow, and fluid that flows within lymphatic vessels

 

Lymphatic system functions include

Drain excess interstitial fluid and places it back to the blood to help maintain blood volume,

transport dietary fats,

carry out immune responses by attacking abnormal cells.

Lymphatic vessels begin as

lymphatic capillaries

Lymphatic capillaries are located between

cells of many tissues

Lymph trunks include the

lumbar,

intestinal,

bronchomdiastinal,

subclavian, and jugular trunks.

Excess filtered fluid becomes

becomes lymph plasma

Muscle and respiratory pumps work to help move

the lymph

Primary lymphatic organs are organs where

immune stem cell divide and become immunocompetent

Immunocompetent

capable of mounting an immune response

Primary organs

red bone marrow (matures B cells and Pre T cells) and

Thymus (gland where T cells become mature)

Secondary organs

lymph nodes (600 total-filter the substances that travel through the fluid),

Spleen (fights invading germs in the blood),

Lymphatic nodules (Develop into memory B cells that will remember and fight off re-exposed pathogens)

Parenchyma

functioning part of the lymph nodes

Spleen functions

remove by macrophages dead/worn out cells,

store platelets,

and production of RBC’s during fetal life

Lymphatic nodules

masses of lymphatic tissue that are not surrounded by a capsule

Lamina propria (connective tissue)

Two lines of defense of innate immunity

skin and mucous membrane, internal defense

We are born with this kind of immunity

Mechanical defenses

skin, mucous membranes, tears, saliva

Chemical defenses

sebum, lysozyme, gastric juice, perspiration

Internal defenses

antimicrobial proteins,

phagocytes (cell that kills),

natural killer cells,

inflammation, fever

Phagocytosis

cell that uses its membrane to engulf a pathogen and prepare to destroy

5 stages of phagocytosis

chemotaxis (chemical response to move phagocyte to location of danger),

adherence (phagocyte connects to the microbe),

ingestion (engulfing the microbe),

digestion (lysosome breaks down the microbe’s cell wall to destroy),

killing (the microbe dies off and remaining pieces are not strong enough to survive or replicate). 

Inflammation

body’s natural responses to tissue damage

PRISH

pain, redness, immobility, swelling, heat

Adaptive immunity

body’s ability to defend itself against specific invading agents

Antigens

substances recognized as foreign that provoke immune responses

Adaptive immunity has both

specificity and memory and is divided into two types

Cell – mediated – T cells

directly attack invading agent

Antibody-mediated – B cells

transform to antibodies to promote immune response

Cell mediated immunity is effective against

bacteria, viruses

Immunology

examines the responses of the body when challenged by the antigens and work towards specificity and memory

Immunogenicity

ability to provoke an immune response by producing specific antibodies

Reactivity

ability of the antigen to react specifically with the antibodies or cells it provoked

For an immune response to occur,

B and T cells must recognize that a foreign antigen is present

B cells can recognize and bind to antigens in

lymph, interstitial fluid, or blood plasma

T cells only recognize fragments of

antigenic proteins that are processed and presented in a certain way

Antigen presentation

antigen enters body and presents itself and looks for a host cell

Cytokines

small protein hormones that stimulate or inhibit many normal cell functions

Interleukin

speed up or slow down processes

Interferons

inhibit viral replication in uninfected cells

Macrophage migration inhibiting factor

prevents macrophages from leaving site of function.

In cell -mediated immunity

antigen is presented,

small number of t cells proliferate and differentiate into a clone of effector cells,

antigen is eliminated

In antibody – mediated immunity

antigen is recognized, t cells costimulate the b cell, antigen is eliminated

IgG

chains of amino acids & carbs that have binding sites for the antigen

Immunological memory

after the first exposure, response is much quicker and more intense,

second exposures will be attacked withing min to hrs

Deletion

b cells undergo apoptosis and die

Anergy

b cells remain alive bit are unresponsive to stimulation

autoimmune disease

T–cells loss of self -tolerance

destruction of b cells + antibodies

B-cells – loss of self-tolerance

PNI

field that deals with pathways that link the nervous, endocrine, and immune systems