TOPIC: Immunity
AIM: How does the immune system protect the body against disease?
DO NOW –
Immune System
- protects body against disease
Pathogen
- Disease causing organism
- microorganisms: bacteria, viruses, parasites, or fungi
Immune Response
- Body recognizes and defends itself
Antigen
- Triggers immune response
- Found on pathogens
The Body’s Lines of Defense
1. Physical Barriers
- keep pathogens out
- skin, saliva, mucus, cilia, tears, sweat, gastric juice
2. Inflammatory Response
- WBC’s (phagocytes) destroy pathogens
3. Antibodies
- Proteins
- Help destroy pathogens (SPECIFIC)
- Attach to antigen slow it down WBC kills it
How are antibodies produced?
- WBC’s
- T-cells tell B-cells to make antibodies
2 types of Diseases
1.Infectious
- pathogens transmitted to others
- Cold, flu, AIDs
2. Noninfectious
- cannot be spread, no pathogen
- Diabetes, cancer
AIDS
- Acquired Immune Deficiency Syndrome
- Infectious
- HIV (Human Immunodeficiency Virus)
- Damages immune system:
- Destroys T-cells (can’t fight pathogens)
TRANSMITTED BY BODY FLUIDS
1. Infected blood 3. Sexual contact
2. Sharing needles 4. Mother fetus
Allergies
- Immune response to substances you are allergic (sensitive) to
- Allergen = what you are allergic to(pollen, dust, etc)
- Histamines produced(cause symptoms)
CANCER
Noninfectious
Abnormal cells grow & divide uncontrollably
May form tumors
IMMUNITY
- Ability to resist infection
2 TYPES OF IMMUNITY
1. Active Immunity
- Produce your own antibodies
- Long term/Permanent
- Acquired by:
a. Contact with pathogen
b. Receiving vaccination: injection of weak or dead pathogen
How does a vaccine work?
A. Vaccine injected
B. Antibodies & memory cells made
C. Antibodies help fight pathogen
D. Memory cells stay in blood & quickly make antibodies if exposed to same pathogen
2. Passive Immunity
- Receive antibodies from another
- Temporary
- Ex: Child gets antibodies in womb & breastfeeding
- Receive antibodies orally or by injection