1. Mrs. Pittaluga 8th Grade Science
Agents of Disease
Mrs. Pittaluga
8th Grade Science

2. Viruses
H1N1 Virus

3. Characteristics Nonliving Neither a prokaryote or an eukaryote
Prokaryote – no nucleus or other defined organelles
Eukaryote – nucleus and defined organelles
Varicella Virus – Chicken Pox

4. Other Characteristics
Neither a heterotroph nor an autotroph
Reproduces by invading host cells
Two parts:
Protective protein outer coat (called the capsid)
Inner core that stores genetic material
Because viruses are non-living, antibiotics are ineffective.
Immunizations help prevent viral infections
Anti-virals are typical method of treatment (Tamiflu)

5. Method of Infection
Invades a cell and reproduces inside the cell until it splits open and destroys the cell
How Viruses Attack

7. Common Viruses Common Cold Flu – H1N1 (Swine Flu), Bird Flu (H5N1)
HIV/AIDS
Chicken Pox/Shingles
Polio
Rabies

8. Bacteria Living Prokaryote – no nucleus Single celled organism
Good and bad bacteria

9. Other Characteristics
Both heterotrophs and autotrophs
Heterotrophs gain their food from other organisms or from food other organisms make.
Autotrophs gain their food by capturing and using the sun’s energy
Rapid growth by means of either asexual (binary fission) or sexual reproduction (conjugation).
Different shapes – spiral, round, rod-shaped
There are approximately five nonillion (5 x 1030) on Earth
The study of bacteria is bacteriology, a branch of microbiology

10. Shapes of Bacteria 3 primary shapes Spherical (cocci/coccus)
Streptococcus (Strep throat, Scarlet fever, pneumonia)
Rod-shaped (bacilli/bacillum) – Most common shape
Salmonella
Lactobacillus acidophilus (yogurt)
Spiral (spirilli/spirillum)
Cholera
Lyme Disease

11. Method of Infection Some bacteria invade cells directly
Some bacteria produce toxins which damage cells
Can be treated with antibiotics
Amoxicillin (Amoxil)
Ciprofloxacin (Cipro)
Azithromycin (Zithromax)
Trimethoprim/Sulfamethoxazole (Septra)
Cholera Bacteria

12. Diseases Caused by Bacteria
Strep Throat
Tuberculosis
Anthrax
Bubonic Plague
E. Coli
Necrotizing Fasciitis (“Flesh- eating bacteria”) – Streptococcus pyogenes
Acidophilus (good bacteria)
E. Coli Bacteria

13. Protists
The Kingdom of Protists are kind of like the misfits. They contain a variety of characteristics that do not place them in any of the other kingdoms of life. (Monera – bacteria, Fungi, Plantae and Animalia)

14. Protists Living Eukaryotes – they do have a nucleus 3 primary types
Plant-like
Animal-like
Fungus-like

15. Other Characteristics
Usually grow in wet places
Most are heterotrophs
Three forms of movement
Flagella
Pseudopods
Cilia
Some are parasites to humans

16. Method of Infection Drinking contaminated water
Eating contaminated food
Sustaining an insect bite

17. Diseases Caused by Protists
Malaria (Plasmodium)
Giardiasis (Giardia intestinalis)
Amoebic dysentary (Entamoeba hystolica)
African Sleeping Sickness (Trypanosoma)

18. Fungi

19. Characteristics Living Eukaroyotes Heterotrophs
Use spores to reproduce
Are decomposers
Live in damp, warm places
Some are parasites to humans

20. Classification of Fungi
Club Fungi Sac Fungi Zygote Fungi

21. Methods of Infection
Spores from an infected person can survive on damp surfaces (showers) and infect skin
Growth on skin:
Asexual reproduction – budding
Sexual reproduction – Hyphae of two fungi grow together and exchange genetic material

22. Diseases Caused by Fungus
Fungal Meningitis (not contagious)
Jock Itch –Tinea cruris
Athlete’s foot
Ringworm

23. Helminths
Multicellular organisms with a physiology that is similar to humans so they are difficult to treat
Diseases include:
Schistosomiasis (caused by the Schistosoma flatworm)
Trichinosis (caused by the Trichinella spiralis roundworm)
Guinea worm disease (caused by Dracunculus medinensis roundworm)

24. Prions New classification of pathogen (last few decades)
Infectious Proteins
Diseases include:
Creutzfeldt-Jakob disease (CJD) in humans
Scrapie in sheep
Bovine spongiform encephalopathy (“mad cow disease”) in cattle