Agenda 4/7

• Warm up #4 • Collect Science Notebook • Notes: Immune System• Microviewers Lab: harmful Bacteria• Crossword puzzle

Warm up 4: Intro to Immune System

1. How do we fight off bacterial infections?2. How can we prevent viral diseases?3. What does it mean to be immune to

something?4. What do you suppose the job of the immune

system is?

Immune System

Let’s Get Defensive

I. Pathogens Cause Infectious Disease

A. Infectious disease1. Caused when a pathogen is passed from one

organism to anotherB. Pathogens

1. Bacteria2. Viruses3. Fungi4. Parasites5. Protozoans

Parasitic Pathogens

Example: Botfly

https://www.youtube.com/watch?v=KNDG7WPtVO4

Pathogenic ProtozoaGiardia:occurs by swallowing contaminated water, by eating contaminated food or through person-to-person contact

https://www.youtube.com/watch?v=bGMor71WkFc

Music video: https://www.youtube.com/watch?v=2R7fTTsXQzY

II. Spread of Disease

A. Types of Reservoirs1. Human (Direct or Indirect Contact)

i. Main reservoir for pathogens that affect humansii. Individual that is symptom-free but capable of

passing the pathogen is called a carrier

II. Spread of Disease Cont.

2. Animal (Vector)i. Other animals also are reservoirs of pathogens that

can be passed to humans, such as influenza and rabies.

3. Others (Direct Contact)ii. Soiliii. Contaminated water or food

III. Treating and Fighting Disease

A. Antibiotic is a substance that can kill or inhibit the growth of bacteria1. Penicillium (bacteria)2. Erythromycin (fights

Diphtheria) 3. Neomycin (creams,

ointments, and eye drops)

4. Gentamicin (helps fight UTIs)

Diphtheria

Agenda 4/8

1. Warm up 52. Notes: Immune System 3. Documentary BBC Horizon: Pandemic Diseases

*Homework: Crossword puzzle (extension… Thursday) *Warrior Lab Friday

Warm up 5: Infectious Disease

1. What is an infectious disease?2. What is a pathogenic reservoir? 3. What are 3 types of pathogenic reservoirs?

Give an example for each.4. A botfly is considered what type of

pathogen? What about Giardia?

I. Immune Response

A. purpose of the immune response is to inactivate or destroy pathogens, abnormal cells, and foreign molecules

II. Nonspecific Immunity

A. Body has a number of defenses in the immune system that fight off pathogens

B. Defenses are nonspecific 1. Not aimed at a specific pathogen

C. Help prevent disease

D. Help slow progression of disease

Immune System

III. Antibodies

A. a protein produced by plasma cells that is used in the immune system to identify foreign objects such as bacteria and viruses

IV. Skin Barrier A. Skin cells

1. protect against invasion by microorganisms

B. Bacteria that live symbiotically on the skin digest skin oils to produce acids

1. Inhibit many pathogens

Immune System

V. Chemical Barriers

A. Saliva, tears, and nasal secretions contain lysozyme (enzyme)

1. Breaks down bacterial cell walls and kills pathogens

B. Mucus acts as a protective barrier1. Blocks bacteria from sticking to inner

epithelial (skin) cells

Immune System

VI. Nonspecific Responses to Invasion

A. Body has nonspecific immune responses to pathogens that get beyond its barriers 1. Cellular defense

i. Phagocytosis – release enzymes or other chemicals to destroy pathogen

2.Interferon (protein)i. Virus infected cells; prevents replication

3. Inflammatory responsei. More blood flow brings in more white blood cells

Immune System

Pandemic Diseases

https://www.youtube.com/watch?v=jESeN63qNcM

Agenda 4/9

1. Warm up 52. Notes: Specific Immunity3. Documentary BBC Horizon: Pandemic

Diseases

*Homework: Crossword puzzle (due tomorrow) *Warrior Lab Friday

Warm up 6: Nonspecific Immunity

1. What is our body’s first defense against microorganisms?

2. What are the chemical barriers our body produces?

3. If microorganisms get past your first line of defenses what do you suppose will happen next?

4. What is the purpose of phagocytosis, and how does it work?

VII. Specific Immunity

A. Lymphatic system 1. Organs and cells

i. Filter lymph and blood

ii. Destroy foreign microorganisms

2. Defend body against infections

Immune System

Immune System

VIII. Lymphatic Cells

A. Lymphocytes – white blood cell that is produced in red bone marrow1. Protect the body

i. T cells (T lymphocytes) • Manage immune response• Directly attack and destroy infected cells

ii. B cells (B lymphocytes)• Differentiate into plasma cells that secrete antibodies (mark antigens,

aka name tags, for destruction)

B. Macrophages – phagocytize foreign matter and activate T cells

https://www.youtube.com/watch?v=7VQU28itVVw

Immune System

A. Temporary protection1. Occurs when antibodies are made by other people or

animals and are transferred or injected into the body i. Between mother and infantii. To treat tetanus and rabiesiii. To inactivate snake and scorpion venoms

IX. Passive Immunity

X. Active Immunity

A. Active immunity occurs after immune system is exposed to disease antigens

1. Memory cells are produced2. Can result from having an infectious disease

B. Immunization1. Deliberate exposure of the body to an antigen2. Primary response and immune memory cells

develop

Immune System

XI. Immune System Failure

A. Some diseases can affect the immune system’s effectiveness1.Acquired Immunodeficiency Syndrome (AIDS)2. HIV infects mainly helper T cells

i. Helper T cells become HIV factories, producing new viruses

ii. Number of helper T cells in an infected person decreases

Immune System

Pandemic Diseases

https://www.youtube.com/watch?v=jESeN63qNcM