The Defence System Flashcards
Pathogens
a disease causing organism
antigen
a forgein particle that stimulates the production of anitbodies
human defense system
all the way the human body protects against antigens
antibodies
proteins produced by lymphocytes in response to an antigen
Name organs of the defense system
thymus. endorince gland
spleen
tonsils
name examples of diseass
measles-virus
cholera- bacteria
malaria-protista
ringworm- fungi
What is the general defense system
barrier system which stops pathogens from entering the body
describe methods of the first line of defense
skin- physical barrier, produces sebum which contains chemicals which kill MO and stops skin drying out and cracking
mucous membranes- found in lining of respiatory and digestive system- produce mucus which traps forgein particles
Acid -HCl
lysozyme- antibacterial enzyme in swaet, tears and saliva
pre blood stream
describe methods of the second line of defense
monocytes (phagocytes and macrophages) they are types of white blood cells that engulf pathogens
complement proteins- cause abmnormal cells to burst
interferons-defence proteins that attack viruses
inflammation- histamine production as a protection mechnianism
fevel- high body temp to prevent MO from forming
2- in blood stream
what is the specific defense system
targets one type of pathogen/ antigen only
will one antibody work on mulitable pathogens
no, one particular antigen will only cause the ptoduction of one paticular antibody which will work on one ptaticular pathogen
how do antibodies destroy pathogens
causing them to be clumped together to be engulfed by macrophages and phagocytes
triggering the complement system - causing abnormal cells to burst
preventing poathogens from entering cells
what are the two types of lymphocytes
B-cells
T-cells
where is the b-cells made and matured
made in red bone marrow
matured in red bone marrow
where are T - cells made and produced
made in red bone marrow, matured in thymus gland
explain the function of the B cells
recognise antigens.
produce antibodies, leads to resistance for life ( b cells produce antibodies in response to an antigen being detected)
some remain as memory cells, they ccause production of antibodies very quickly.
explain function of T cels
4 types of t cells
helper cells -> recognise an antigen, stimulate B cell production + activate killer cells
killer cells- secrete chemicals (peforin ) into cells causing them to burst
supressor cells- when antigens have been destroyed, supressor cells stop the production of B cells and Killer cells
memory cells- remember the antigen so if it reappears the stimulation of killer cells and B cells will be much faster next time around.
immunisation
resistance / protection against pathogens by vaccination
immunity
resistance against infection/ pathogens
vaccine
small done of an inactive (dead/ non diease causing) virus that stimulates a immune response
vaccination
adminstration ( injection) of a non-diease causing dose of a pathogen/ virus that stimulates an immune response
antibiotics
Chemicals produced by microrganisms used to kill other microrganisms
what is induced immunity?
using antibodies to resist specific diseases
types of induced immunity
active immunity and passive immunity
what is active immunity
antibodies prodiced internally by living organism
types of active immunity
natural immunity
artificial immunity
what is natural active immunity
the body produced antibodies in response to being exposed to an antigen
what is artificial active immunity
immunisation/ vaccine
dead/ inactive antigens are sdmistrated which cause the body to respond by producing antibodies. the body is able to react if that antigen reappers again
what is passive immunity
obtain antibodies from another living organism
what is natural passive immunity
when antibodies enter the body in natural ways eg mother passes on antibodies she has to the baby through breast milk/ placenta
what is articifial passive immunity
a course of perscribed antibiotics,
anti tetanus shot
Out of active immunity and passive immunity , which one is more long term and explain
active immunity is more long term as memory cells remain in the body. if the same indection occours again.They recognise the antigen and cause the production of large amounts of specific antibodies quickly
passive immunity is short term as the antibodies given do not have memory cells
auto immune disease
when the defense system attacks normal body cells.
eg Type 1 diabetes
will perscribing antibiotics for a viral infection work?
NO
a viral antigen is a parasite and only lived inside a host cell. antibodies will only work if the antigen is outside the host cell. the viral isnt exposed to the antibiotic therefore antibodies arnt produced.
