AP Biology Immune System WBC attacking cancer cell lymph system

Regents Biology Vocabulary of Immunity Disease  Any condition that disrupts the homeostasis of an organism. Pathogen  Foreign organisms that cause disease. (microorganisms)

Regents Biology 1. Pathogens 2. Toxins in the environment 3. Inheritance… Gee thanks, mom! What causes disease?

Regents Biology Pathogens of Disease VirusCommon Cold, Influenza, HIV, Chicken Pox, Measles BacteriaStrep Throat, Syphilis, E-coli, Food Poising FungusAthletes foot, Ringworm ParasitesLeeches, Tapeworms, Malaria, Lyme Disease

Regents Biology Other Causes of Disease Cause of DiseaseExamples Inherited DisordersDown Syndrome, Cystic Fibrosis, Sickle Cell Anemia, Type 1 Diabetes Exposure to toxinsExposure to asbestos -> Mesothelioma Lead poisoning, radiation poisoning Poor nutritionScurvy, Blindness, Lack of Iodine (Goiter) Organ malfunctionsHear Attack, Diabetes, Stroke High risk behaviorsLung Cancer, Drug Addiction, Skin Cancer, STD’s

Regents Biology HOW ARE DISEASES SPREAD?  Coughing  Sneezing  Physical Contact (Saliva, Blood, Bodily Fluids, Skin Contact)  Contaminated Food or Water  Infected Animals (Vectors)

Regents Biology To protect and defend the body against pathogens The Immune System

Regents Biology How does the Immune System Work? 2 ways: 1. Nonspecific defenses- Tries to keep everything OUT!  Skin, mucus, cilia, tears, stomach acid, saliva, sweat 2. Specific Defenses- Fights off infection once the pathogen gets inside the body.  White Blood Cells (WBC’s)

Regents Biology If the pathogen gets inside anyway, there are things your body usually does to try to slow the invader down… 1. Increased Body Fever: Denatures pathogen’s proteins 2. Expanding blood vessels: (red and warm) Increased blood flow to area = More RBC’s & clotting factors for repair = More WBC’s to fight bacteria (pus) Inflammation

Regents Biology Antigen  chemical name tags on the surface of every cell = Protein The body recognizes invaders! disease-causing bacteria disease-causing virus one of your own cells antigens say: “I belong here” antigens say: “I am an invader”

Regents Biology  Some kill pathogens  Some produce antibodies White Blood Cells AKA: leukocytes, lymphocytes, plasma cells, eosinophils, neutrophils, basophils, monocytes, macrophages

Regents Biology  Patrolling B cells  make antibodies against invader immediately  Memory B cells  remembers invader  can make antibodies quickly the next time! B cells

Regents Biology Antibodies- proteins that either kill invaders or mark them for killing Antibodies are SHAPE SPECIFIC to pathogens!

Regents Biology B cells immune response invader (foreign antigen) Y Y Y Y Y Y Y Y Y Y Y Y B cells Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Memory B cells Y Y Y Y Y Y Y Y Y Y Y Y Y Patrolling B cells Make & release antibodies recognition Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Antibody “fits” with antigen Antibodies already in blood

Regents Biology The antibody tag says “this is an invader”  quick…eat him! Antibodies: macrophage eating tagged invaders invading germs tagged with antibodies Y Y Y Y Y Y Y B cells releasing antibodies Y Y Y Y Y Y Y Y Y Y Y Y Y Y

Regents Biology T Cells  Helper T Cells: Notifies other WBC’s of invasion!  Killer T Cells: Hunts down pathogens & destroys them!

Regents Biology 1. Exposure to harmless version of a pathogen “dead”, weakened Vaccinations

Regents Biology 2. Immune response produces antibodies to mark and destroy the invading pathogen! Antibodies = Shape Specific!! 3. Antibody production guarantees a rapid immune response if there is future exposure to the SAME pathogen!  Most successful against viral diseases  Ex: flu, chicken pox, HPV, MMR, swine flu, whooping cough, polio, small pox Vaccinations

Regents Biology Immunity  Immunity = the condition your body has when it already knows how to make the antibodies for a specific disease.  If you get sick with an illness and fight it off, you can’t get the same illness again  Pathogen is recognized! Helper T cells signal the immune system to respond! B cells make antibodies. Killer T cells start killing!

Types of Immunity Active Immunity  Occurs when a organism is: 1. infected with a disease or 2. gets a vaccine  The organism makes it own antibodies specific to antigen  This type of immunity last a life time (stimulates B cells to make antibodies if re- exposed)

Regents Biology Types of Immunity Passive Immunity  Antibodies made by another organism (not you!)  Only last a short time (~1 month, your body will eventually destroy the borrowed antibodies)  Ex: Babies will receive antibodies from their mother when they breastfeed.  Ex: Travelers to foreign countries can get antibodies (injected) against tropical diseases.

Regents Biology Curing You of Disease Antibiotics = medicine Ex: Penicillin, Streptomycin, Tetracycline. Advantage  kill bacteria that have successfully invaded you, without harming your cells Disadvantages  use only after sick  only good against bacteria  possible development of resistance by bacteria (if don’t use correctly) – ALWAYS TAKE THE ENTIRE Rx  can get sick again by the same pathogen

Regents Biology Disruption of Homeostasis… Auto-Immune Diseases Immune system attacks body cells  lupus  antibodies attack many different body cells  rheumatoid arthritis  antibodies cause damage to cartilage & bone  diabetes  insulin-making cells of pancreas are attacked & destroyed  multiple sclerosis  T cells attack myelin sheath of brain & spinal cord nerves  fatal

Regents Biology Allergies The response of the immune system to harmless environmental substances. (It thinks they are pathogens!)  Histamines are the chemicals released to cause the inflammatory response  Ex: Pollen can cause a fever, runny nose, and sneezing  Some allergies can trigger a severe reaction, called anaphylactic shock  This can cause choking due to a constricted airway When things go wrong…

Regents Biology Allergens

Regents Biology Organ Transplants People who are LIVING can donate a Kidney or a PART of THE: Lung, Liver, Intestine, Pancreas Tissues that can be donated are: Cornea (coating of the eyeball), Middle ear, Skin, Heart valves, Bone, Veins, Cartilage, Tendons, Ligaments Organs of the body that can transplanted after death: Kidneys, Heart, Liver, Pancreas, Intestines, Lungs, Skin, Bone marrow, Cornea

Regents Biology Organ Transplants  When a person receives someone else's organ, the organ has foreign antigens on it.  The recipient’s white blood cells will recognize the organ as foreign, think it is a pathogen, and attack it. (Killer T!)  So, the recipient has to take immunosuppressant drugs

Regents Biology Organ Transplants

Regents Biology HIV: Human Immunodeficiency Virus  Infects helper T cells  Helper T cells can’t activate rest of immune system  The body doesn’t hear the alarm AIDS: Acquired ImmunoDeficiency Syndrome  T cell count very low (200 cells/mm 3 instead of the normal )  infections by other (normal) pathogens can cause death Disease of the Immune System

Regents Biology HIV AIDS

Regents Biology AIDS: fatigue diarrhea nausea vomiting fever chills night sweats Death from opportunistic Infections HIV/AIDS Symptoms

Regents Biology HIV/ AIDS Over 33.4 million people are infected with HIV/AIDS worldwide

Regents Biology Transmission of HIV Healthy skin is an excellent barrier against HIV and other viruses and bacteria. HIV cannot enter the body through unbroken skin.

Regents Biology Transmission of HIV