IMMUNITY
Specific defenses:If our body recognizes cells as parts of itself it does not attack them, but if it recognizes as nonself, then it attacks them with antigens.
Humoral immunity and cell-mediated immunity. The main cells that work in these responses are B and T cells.
Humoral immunity: Production of antibodies against an antigen.
B-cells
Memory B-cells: Create a memory in which our body remembers how to fight certain pathogens
Lymphocyte B-cells: Mediate the production of antigens
T-cells
Lymphocyte: Secrete antibodies and macrophages to kill infected target cells and destroy microbes
Cytoxic: Kill other infected cells
To eliminate diseases and damaged cells, macrophages innate and secrete antimicrobial and pro-inflammatory mediators.
Immunity is the ability of an organism to resist an infectious disease or pathogen.
Infectious diseases are the result of the disruption of normal body functions. Pathogens are one of the main producers of diseases.
Pathogens are organisms that cause a disease. Some pathogens are: bacteria, fungi, and protists.
They spread through coughing, sneezing, and physical contact.
There are other types of diseases, these are caused by toxins produced by food and water poisoning.
Non-specific defenses: Are divided in two sections; first line and second line
Our body fights against pathogens through specific and non-specific defenses
Cell-mediated immunity: Occurs inside infected cells by activating cytokines and the infected cell goes into lysis.
First line of defense: Is the skin, it creates a physical protective barrier that keeps most pathogens out of the body.
Second line of defense: It starts working when pathogens get inside our body. Includes inflammatory response and fever.
Saliva, mucus, and tear contain lysosome (enzyme), it breaks down bacteria cell walls. Stomach secretions destroy pathogens in food or water.
Inflammatory response causes infected areas to become inflamed, red, and painful. It begins when pathogens stimulate mast cells to release histamines to the affected area, and then white blood cells destroy the bacteria in the infected tissue.
Important molecules, proteins, and cells regarding immunity:
Antigens: Molecule that stimulates an immune response that fight a disease.
Antibodies: A blood protein that counterattacks a specific antigen.
Plasma cells: White blood cells.