1. THE BODY’S DEFENSES AGAINST INFECTION

2. THE BODY’S DEFENSES YOUR FIRST LINE OF DEFENSE- YOUR SKIN AND FLUIDS FORMS A BARRIER BETWEEN YOU AND PATHOGENS. EYES – TEARS WASH PATHOGENS FROM YOUR EYES. TEARS CONTAIN CHEMICAL COMPOUNDS THAT KILL PATHOGENS. SKIN-TOUGH OUTER LAYER OF SKIN PROTECTS YOU FROM PATHOGENS.CUT,BURN, OR SCRAPE. STOMACH- GASTRIC JUICES PRODUCED BY THE LINING OF YOUR STOMACH HELP KILL PATHOGENS THAT ENTER THE BODY THROUGH FOOD OR DRINK.

3. FIRST LINE OF DEFENSE MUCOUS MEMBRANES- LINE YOUR NOSE, MOUTH, AND THROAT AND SECRETE A FLUID CALLED MUCUS THAT TRAPS PATHOGENS. SALIVA-WASHES GERMS FROM YOUR TEETH. SALIVA ALSO CONTAINS CHEMICALS THAT KILL MANY PATHOGENS.

4. THE MAIN LINE OF DEFENSE IMMUNE SYSTEM IS A COMBINATION OF BODY DEFENSES MADE UP OF CELLS, TISSUES, AND ORGANS THAT FIGHT OFF PATHOGENS AND DISEASE. THE IMMUNE SYSTEM HAS TWO MAJOR KINDS OF DEFENSE STRATEGIES-A NONSPECIFIC, OR GENERAL, RESPONSE AND A SPECIFIC RESPONSE. IMMUNITY IS YOUR BODY’S ABILITY TO RESIST THE GERMS THAT CAUSE A PARTICULAR DISEASE.

5. CONTINUE NONSPECIFIC RESPONSE BEGINS WITH INFLAMMATION OR INCREASED BLOOD FLOW, TO THE AFFECTED AREA. INFLAMMATION SIGNALS CHEMICALS MESSENGERS TO SUMMON SPECIAL WHITE CELLS TO SPEED TO THE AFFECTED AREA AND DESTROY INVADING PATHOGENS. IF PATHOGENS SPREAD, THE INFLAMMATION MAY RESULT IN A FEVER.

6. SPECIFIC RESPONSE IF THE PATHOGENS SURVIVE THE NONSPECIFIC RESONSE, A SPECIFIC RESPONSE IS SET IN MOTION. THE RESONSE TARGETS THE PATHOGENS IN A MORE SPECIALIZED MANNER. IT ALSO GIVES THE BODY THE ABILITY TO RECOGNIZE THE SAME PATHOGEN IF IT INVADES AGAIN.

7. NONSPECIFIC RESONSE` NONSPECIFIC RESPONSE IS ALL-PURPOSE RESPONSE LAUNCHED BY THE IMMUNE SYSTEM. IT BEGINS WITH INFLAMMATION, OR INCREASED BLOOD FLOW TO THE AFFECTED AREA. INFLAMMATION SIGNALS CHEMICAL MESSENGERS TO SUMMON SPECIAL WHITE BLOOD CELLS TO SPEED TO THE AFFECTED AREA AND DESTROY INVADING PATHOGENS.

8. THE LYMPHATIC SYSTEM AND IMMUNE RESPONSE THE LYMPHATIC SYSTEM IS A SECONDARY CIRCULATORY SYSTEM THAT HELPS THE BODY FIGHT PATHOGENS AND MAINTAIN ITS FLUID BALANCED. THE LYMPHATIC SYSTEM CARRIERS A FLUID KNOWN AS LYMPH AND PRODUCES WHITE BLOOD CELLS.

9. CONTINUE B-CELLS AND T- CELLS ARE INVOLVED IN THE SPECIFIC IMMUNE RESPONSE. B-CELLS ARE FORMED IN THE BONE MARROW, AND T-CELLS ARE PRODUCE IN THE THYMUS GLANDS. ANTIGENS ARE SUBSTANCES RELEASED BY INVADING PATHOGENS. B-CELLS RELEASE ANTIBODIES, PROTEINS THAT ATTACH TO ANTIGENS, KEEPING THEM FROM HARMING THE BODY.

10. LYMPHATIC SYSTEM CONTINUE T-CELLS ATTACK PATHOGENS AND STIMULATE THE PRODUCTION OF B-CELLS. THERE ARE TWO MAIN TYPES OF T-CELLS. KILLER TCELLS ATTACH TO THE INVADING PATHOGENS AND DESTROY THEM. HELPER CELLS ACTIVATE THE PRODUCTION OF ANTIBODIES BY B-CELLS.

11. IMMUNITY NATURAL IMMUNITY IS PRESENT AT BIRTH, AND INCLUDES THE SKIN AND MUCOUS MEMBRANES AND OF WHITE BLOOD CELLS. ACQUIRED IMMUNITY DEVELOPS OVER A PERSON’S LIFETIME..