Pack 6

PATHOGEN = CAUSES INFECTION E.G. BACTERIA, VIRUS

WHITE BLOOD CELLS = DEFEND BODY IN CELL MEDIATED USING T LYMPHOCYTES AND HUMOURAL USING B LYMPHOCYTES RESPONSES

LYMPHOCYTES = DISTINGUISH BETWEEN SELF AND NON-SELF SUCH AS PATHOGENS TOXINS OR ABNORMAL BODY CELLS, PROTEINS ON CELLS ALLOW THEM TO BE IDENTIFIED, EACH TYPE OF CELL HAS SPECIFIC PROTEINS COMPLEMENTARY TO THE PROTEINS ON THE LYMPHOCYTE

CLONAL SELECTION = LYMPHOCYTE RECOGNISES A PATHOGEN ANS IS STIMULATED TO BUILD ITS NUMBERS

PHAGOCYTOSIS = PHAGOCYTES INGEST PATHOGENS:

1) CHEMICAL PRODUCTS OF PATHOGEN ATTRACT PHAGOCYTE

2) RECEPTORS ON PHAGOCYTE ATTACH TO CHEMICALS ON SURFACE OF PATHOGEN

3) PHAGOCYTE ENGLUFS PATHOGEN FORMING PHAGOSOME

4) LYSOSOMES IN LYSOSYMES MIGRATE TOWARDS PHAGOSOME AND RELEASE LYSOSYMES INTO PHAGOSOME TO HYDROLYSE THE PATHOGEN

5) PRODUCTS OF HYDROLYSIS ABSORBED BY PHAGOCYTE

ANTIGEN = ANYTHING RECOGNISED AS NON-SELF, USUALLY PROTEINS ON CELL SURFACE, PRESENCE TRIGGERS ANTIBODY PRODUCTION

T LYMPHOCYTES = ANTIGEN PRESENTING CELLS DISPLAY FOREIGN ANTIGENS ON THEIR SURFACE, T CELLS RESPOND TO ANTIGENS  (CELL MEDIATED IMMUNITY)

1) PHAGOCYTE PRESENTS PATHOGENIC ANTIGENS ON SURFACE

2) RECEPTORS ON SPECIFIC HELPER T CELLS COMPLEMEMTARY TO ANTIGENS

3) ATTACHMENT ACTIVATED T CELL TO DIVIDE RAPIDLY

4) CLONED T CELLS STIMULATE CYTOTOXIC T CELLS, B CELLS TO DIVIDE AND SECRETE ANTIBODIES SPECIFIC TO THE ANTIGEN, AND MEMORY CELLS

CYTOTOXIC T CELL = KILL ABNORMAL CELLS BY PRODUCING PROTEIN PERFORIN TO MAKE HOLES IN CELL MEMBRANE SO CELL AFFECTED BY WATER POTENTIAL

B CELLS = PRODUCE SPECIFIC COMPLEMENTARY ANTIGEN TO THE ANTIBODY, FORM ANTIGEN-ANTIBODY COMPLEX

MONOCLONAL ANTIBODY = SPECIFIC ANTIBODY MADE BY EACH CLONE

CLONAL SELECTION = T HELPER CELLS BIND TO ANTIGENS STIMULATING B CELLS TO DIVIDE TO FORM CLONES

1) B CELL TAKES UP AND PRESENTS ANTIGENS ON ITS SURFACE BY ENDOCYTOSIS

2) T HELPER CELLS ATTACH TO ANTIGENS ACTIVAATING B CELLS TO DIVIDE INTO PLASMA CELLS

3) PLASMA CELLS SECRETE SPECIFIC ANTIBODY TO THE ANTIGEN WHICH ATTACHES, DESTROYING THE PATHOGEN IN PRIMARY RESPONSE

4) SOME B CELLS DEVELOP INTO MEMORY CELLS FOR SECONDARY RESPONSE

ANTIBODY = PROTEIN WITH 4 POLYPEPTIDE CHAINS AND SPECIFIC BINDING SITES SYNTHESISED BY B CELLS, SPECIFIC ANTIBODIES HAVE COMPLEMENTARY BINDING SITE TO SPECIFIC ANTIGEN FORMING ANTIGEN-ANTIBODY COMPLEX, BINDING SITES DIFFERENT FOR EACH ANTIBODY (VARIABLE REGION)

AGGLUTINATION = ANTIBODIES CLUMP CELLS TOGETHER TO EASIER FOR PHAGOCYTES TO DETECT THEM, SERVE AS MARKERS TO STIMULATE PHAGOCYTES TO ENGLUF BACTERIA

MONOCLONAL ANTIBODIES = CAN BE USED TO TARGET SPECIFIC CELLS, E.G. CANCER INDIRECT MONOCLONAL ANTIBODY THERAPY INVOLVES RADIOACTIVE CYTOTOXIC DRUGS REDUCING SIDE EFFECTS OF CHEMOTHERAPY, USED TO DIAGNOSE DISEASE

PREGNANCY TESTING = ANTIBODIES USED, IF HORMONE PRESENT IT BINDS TO ANTIBODY SHOWING COLOUR

PASSIVE IMMUNITY = ANTIBODIES FROM OUTSIDE SOURCE USED, NO DIRECT CONTACT WITH PATHOGEN, NO MEMORY CELLS FORMED

ACTIVE IMMUNITY = STIMULATING PRODUCTION OF ANTIBODIES USING THE IMMUNE SYSTEM, DIRECT CONTACT WITH PATHOGEN, LONG LASTING IMMUNITY. CAN BE NATURAL (INFECTED UNDER NORMAL CIRCUMSTANCES) OR ARTIFICIAL (VACCINATION INDUCES IMMUNE RESPONSE)

VACCINATION = INTRODUCTION OF APPROPRIATE DISESE ANTIGENS INTO THE BODY STIMULATING AN IMMUNE RESPONSE TO PRODUCE MEMORY CELLS TO FIGHT FUTURE INFECTION

HERD IMMUNITY = LARGE POPULATION VACCINATED MAKING IT HARD TO SPREAD, HARD TO ELIMINATE A DISEASE BECAUSE VACINES NOT EFFECTIVE IN CERTAIN PEOPLE AND THE PATHOGEN MAY MUTATE FREQUENTLY, IMPOSSIBLE TO VACCINATE AGAINST ALL STRAINS OF A PATHOGEN

ETHICS = VACCINE PRODUCTION INVOLVES ANIMALS, CAN HAVE SIDE EFFECTS

STRUCTURE OF HIV = REVERSE TRANSCRIPTASE, RNA, CAPSID, MATRIX, LIPID ENVELOPE, ATTACHMENT PROTEINS

 REPLICATION OF HIV = 

1) PROTEIN ON HIV BINDS TO PROTEIN ON T HELPER CELL, CAPSID FUSES WITH MEMBRANE, RNA AND ENZYMES IN HIV ENTER CELL

2) REVERSE TRANSCRIPTASE CONVERTS RNA TO DNA, INSERTED INTO HOSTS DNA

3) HIV DNA CREATES mRNA INSTRUCTING CELL TO MAKE NEW VIRAL COMPONENTS

4) HIV PARTICLES BREAK AWAY FROM CELL USING MEMBRANE AS LIPID ENVELOPE

HIV = CAUSES SYMPTOMS OF AIDS AS IT ATTACKS T HELPER CELLS SO THE IMMUNE SYSTEM CAN'T STIMULATE B CELLS TO PRODUCE ANTIBODIES SO MORE LIKELY TO GET AN INFECTION. ANTIBIOTICS INEFFECTIVE AGAINST VIRUSES AS THEY DON'T HAVE METABOLIC MECHANISMS OR CELL STRUCTURES TO DISRUPT

ELISA TEST = USES ANTIBODIES TO DETECT PRESENCE OF PROTEINS

1) APPLY SAMPLE TO SURFACE TO WHICH ANTIGENS WILL BIND, WASH OFF EXCESS

2) ADD ANTIBODY SPECIFIC TO ANTIGEN BEING DETECTED, WASH OFF EXCESS

3) ADD SECOND ANTIBODY WITH ENZYME ATTACHED TO BIND TO FIRST ANTIBODY, WASH OFF EXCESS

4) ADD COLOURLESS SUBSTRATE OF ENZYME, IF ENZYME PRESENT COLOUR SHOWN, MEANING ANTIGEN IS PRESENT

5) AMOUNT OF ANTIGEN PRESENT RELATIVE TO COLOUR INTENSITY