Immune System Protecting you whether you know it or not!!!!

Immune System Fights off Infections and diesases

Function Of the Immune System Helps kills all bad cells Keeps body healthy when sick

Immune system Structure Skin Hair Nails Glands White blood cells

Immunity Process of producing cells that inactivate foreign substances. Most Common: viruses and bacteria.

Line Of Defense First Line of Defense

Skin

Mucus

Other Defenses 3. Tears 4. Saliva 5. Oil and Sweat Glands

Lysozyme An enzyme that breaks down the cell wall of bacteria. * Found in saliva and tears

2 nd Line of Defense Inflammatory Response A non-specific reaction by the body to injury or infection.

Step # 1 Blood flow to the wounded area increases bringing millions of white blood cells to the scene.

Step # 2 Phagocytes (macrophages) engulf bacteria and viruses near or at the wound area. **** Phagocytes are type of white blood cells.

Step # 3 The battle between the white blood cells and the foreign invaders will produce pus.

Fever The bodies attempt to kill bacteria and viruses by raising the internal body temperature.

Antibodies Use as a Line of Defense Used By the Immune System to identify and fight off foreign objects such as viruses and bacteria

Antibody Structure

Active and Passive Immunity Active immunity Lymphocytes are activated by antigens on the surface of pathogens Natural active immunity - acquired due to infection Artificial active immunity – vaccination Takes time for enough B and T cells to be produced to mount an effective response.

Active and Passive Immunity Natural passive immunity A mother’s antibodies pass across the placenta to the foetus and remain for several months. Colostrum (the first breast milk) contains lots of IgA which remain on surface of the baby’s gut wall and pass into blood

Vaccination Given in weaker form Injection into vein or muscle Oral