Lines of defense

Specific-Immunity

Often occurs alongside nonspecific reactions, such as inflammation or if an infection persists.

Non-specific Immunity

React to any kind of damage, such as physical knock a burn, extreme cold, corrosive chemicals, and living invaders.

First Line of Defence also know as Physical Barriers.

Skin and mucous membranes defend against viral and bacterial invaders. the pH of skin is around 3-5. Lysozyme, an antimicrobial enzyme is secreted through tears, saliva, and perspiration.

Second Line of Defence

Activated if invaders that take up residence within the body. Non-specific defence mechanisms that relies on phagocytosis via macrophage and Inflammation

Phagocytosis/Macrophage

Macrophages ( big eaters) are WBC that has a foreign antigen. The macrophage performs Phagocytosis.

Inflammation/Inflammatory response

Localized, non-specific response triggered when tissue cells are injured by bacteria or physical injury. Characterized by: swelling, heat, redness, and pain.

Temperature

When you are infected with a cold or flu, macrophages will destroy the microbes and release chemicals into the blood. When these chemicals are detected by the hypothalamus (brain), they cause an increase in bodies temperature aka fever. The higher temperature helps prevent the spread (reproduction) of the microbe.

Third Line of Defence

There are two main types of specific immunity: Cell-mediated Immunity and antibody-mediated Immunity.

Cell-mediated Immunity- activation of phagocytes, T cells and the release of various chemicals in response to a foreign antigen.

Antibody-mediated Immunity- Create antibodies in response to a foreign antigen

T Cells

there are four different types of T cells they Helper T cells, Killer T cell, Suppressor T cells, and Memory T cells.

Antibody-Mediated Immunity

The body contains millions of B cells. Located in lymphoid tissue. each response to a specific antigen. Become activated in presence of foreign antigen.

antigen

A protein on a foreign objects that stimulates immune system to produce antibodies.