Immune system
Do now : Homeostasis failure of Homeostasis
Immunity- the bodies ability to fight off disease
Immunity Disease is the failure of Homeostasis - Causes of disease Pathogens –disease causing agent. a . Virus -needs a host to survive. Does not have all the organelles to survive on its own. b. Bacteria c . Fungus S1
- Causes of disease 2. Inheritance 3. Toxic substances- chemicals 4. Poor diet 5. Organ malfunction 6. Personal behavior 7. Radiation
Antigen- any substance capable of stimulating an immune response ex: pathogen Antibody- proteins in the blood that attack antigens or pathogens Antibodies are produced by White Blood Cells (WBC) Antibiotic- A Drug (medicine) to treat bacterial infections-1st discovered in 1928-Penicillin
Defense System - mucus membranes, nose hairs -stomach acid (HCL) 1st line of defense – Physical barriers that prevent invaders from entering the body tissues Examples: - skin - mucus membranes, nose hairs -stomach acid (HCL) -tears, ear wax 2nd line of defense – non-specific (general) White Blood cells engulf bacteria Increased heart rate- so white blood cells can get to infection more quickly Inflammation-redness, fever, swelling, puss
Barriers
Inflammation
white blood cells that eat
3rd line of defense Antibodies and lymphocytes (T-cells, B-Cells) are produced to fight the infection. B and T cells are produced in the Thymus, Spleen, Tonsils, Bone Marrow and Lymph nodes. Immune reactions occur between antibodies and antigens when the immune system defends itself against invading organisms. Examples: 1. Organ transplant rejection 2. Chicken Pox 3. Colds S5
IMMUNE SYSTEM RESPONSE 1. Macrophage (WBC) engulfs antigen and displays antigen on surface. 2. Helper T-cell recognizes the antigen receptors on the macrophage. 3. Helper T-cell stimulates B-cells to make antibodies and gets killer T cells ready. 4. Antibodies bind to antigen and inactivate it
Types of Immunity Active Immunity- the body makes its own antibodies to a particular antigen usually as a result of having the disease (chicken pox). This usually last a long time. Vaccination- injection of a dead or weakened form of the disease causing microorganism. This can stimulate antibody production. Passive Immunity-Temporary immunity to a disease produced by the injection of antibodies (produced by another person or animal) into the body. Examples: People exposed to hepatitis are given an injection containing antibodies Mother passes immunity onto her baby. Lasts about 2 months. Breast fed babies get moms immunities as well. S6
Immune Disorders Allergies – an abnormal immune response to a normal or beneficial substance. examples: pollen, cat or dog hair, peanut butter, bee venom, dust, mold Triggers production of Antibodies - chemicals that attack the antigen S7
A.I.D.S. Acquired Immune Deficiency Syndrome Caused by the H.I.V. virus – which infects the T2 lymphocytes. AIDS weakens the immune system. Thus, the person with AIDS usually dies from an infection that the body cannot fight off anymore.
Protecting you Antibiotics = medicine advantage kill bacteria that have successfully invaded you make you well after being sick disadvantage use only after sick only good against bacteria possible development of resistance by bacteria (if don’t use correctly) can get sick again