Microbiology 120 scsu

Why do we defend ourselves?

Present on or in our bodies
changes over time

don't harm us

can cause disease

microorganisms that may be present in or on the body under certain
conditions and for certain lengths of time; they are easier to remove by
mechanical friction than resident flora

present in all humans
exist from birth
act against all or most pathogens
first line of defense rapid response

activate in response to a pathogen
active against specific pathogens
prevent reinfection

species immunity
behavioral immunity
racial immunity
population immunity

skin
mucous membrane
ciliary movement

lysozomes in saliva and tears
acid in stomach
sticky acidic vaginal secretions

Protein response for virus
protect normal cells from affected cells
alpha beta gamma

produced by almost all cells
especially effective against viral infections

produced by natural killer cells and by specific lymph-nodes

protein infections
non-specific innate and specific immune response
20 different proteins
aggregate from membrane attack complex (MAC)
triggered by antibody binding to microbes
amplifies inflammatory response

Aggregate to form a ___ ____ ____ that inserts into the plasma membrane of the invading cells. Fluid enters the cell through the pore, causing the cell to swell and burst.

White Blood Cells
circulate through body
attack invading microbes within tissue
Granulocytes or Agranulocytes

Granuloes with in cytoplasm
neutrophils
basophils
eosinophils

No granuloes
monocytes
natural killer cells
B & T lymphocytes (specific immune response)

most abundant
eliminate microbes by phagocytosis
short life span
not found in healthy tissue
release chemical that kills bacteria

large irregular shaped cells
kills microbes by phagocytosis
roam the extracellular fluid

process by which neutrophils and macrophages kill pathogens
four steps
*recognition
*engulfment
*destruction
*expulsion

kill cells of the body that have been invaded by viruses and intracellular pathogens
kill by lysis
also kill cancer cells

a molecule that provokes an immune response

respond to antigens by producing proteins called antibodies
bind to antigen

do not secrete antibodies they regulate immune response and also directly attack cells that carry specific antigens
mature in thymus

originate and mature in bone marrow
released to circulate in blood and lymph
recognize specific foreign antigens

Variable region of heavy chain
antigen binding site
variable region of light chain
constant region of heavy chain
constant region of light chain

firs antibody secreted during primary immune response promotes agglutination reaction in blood and extracellular fluids
pentamer

secreted during secondary response most abundant form in blood plasma maternal Ab activates complement
monomer

most abundant form in body secretions breast milk tears saliva mucus
Dimer

present on the surface of B cells as receptors assists in activation of B cells
monomer

promotes the release of histamine which triggers and allergic reaction effective against worms
monomer

originate in bone marrow
mature in thymus
identify micro-organisms by he antigens exposed on their surface

initiate the immune response
T Cells

provide a quick response to previously encountered antigen
T Cell

lyse cells that have been infected by viruses also attack transplanted tissue and cause graft rejection
T cell

terminate the immune response
T cell

abnormal B cell response
occurs within seconds or minutes
IgE mast cells
allergens dust bee sting pollen food
treated with antihistamines

abonormal Ab response IgG & IgM
activation of complement and phagocytosis
transfusion reactions Rh disease of new born

Abnormal Ag-Ab complexes form and deposit throughout the body stimulating complement and phagocytosis
IgG & IgM
systemic lupus
treated with steroids

abnormal T cell response
produces symptoms about 48 hours to weeks after exposure cannot be treated with antihistamines
corticosteroids are used
poison ivy

obtained by injecting an antigen into an animal and later drawing blood effective against a number of antigenic sites

specific for one antigenic determinant site coated onto beads and used in detection test

an agent that kills bacteria

an agent that inhibits growth of bacteria but does not usually kill them

contamination of an object by microbes septicemia is microbial infection of the blood

free of microbial contamination

are natural substances produced by certain groups of microorganisms that kill or inhibit the growth of other microorganisms

are chemically synthesized compounds used in the treatment of infectious diseases

block folic acid synthesis

sulfanilamide

trimethoprim

interfere with synthesis of bacterial cell wall which is not present in eukaryotes
bind to and inhibit enzymes needed for synthesis of peptidoglycan no effect on resting cells lethal to dividing cells

penicillin
cephalosporins
carbapenems

inhibit bacterial protien synthesis
70s ribosomes of bateria is different than that of 80s ribosomes of eukaryotes
bind to small subunite and precent formation of initiation complex

steptomycin
Kanamycin
neomycin
gentamycin
paramomycin

halt protein synthesis in the bacteria
bind to cmall ribosomal subuint and prevent transfer of activated amino acids to the ribosomes thus halting protien synthesis
discoloration of teath broad specturum

chlortetracycline
oxytetracycline
doxycycline