1. BACTERIA vs VIRUS
Biology Chapter 24

2. Bacteria are very small

3. This is a pore in human skin and the yellow spheres are bacteria

4. Bacteria are very small compar-ed to cells with nuclei

5. Evolution/Classification
Most numerous on Earth
Most Ancient
Microscopic Prokaryotes
Evolution has yielded many species adapted to survive where no other organisms can.
Grouped based on:
Structure, physiology, molec. Composition reaction to specific types of stain.
Eubacteria= Germs/bacteria
Archaebacteria

6. Chemosynthetic bacteria use the sulfur in the “smoke” for energy to make ATP.

7. The red color of this snow is due to a blue-green bacteria

8. Kingdom Eubacteria Bacilli – rod-shaped Spirilla – spiral-shaped
Can have one of three basic shapes
Bacilli – rod-shaped
Spirilla – spiral-shaped
Cocci – sphere-shaped
Staphylococci – grape-like clusters
Streptococci – in chains
SHOW ME

9. Bacillus bacteria are rod or sausage shaped

10. Coccus bacteria are sphere or ball shaped

11. Spirillium bacteria have a corkscrew shape

12. Diplo-bacteria occur in pairs, such as the diplococcus bacteria that causes gonorrhea

13. Staphylo - bacteria occur in clumps, such as this staphylococcus bacteria that causes common infections of cuts

14. Strepto- bacteria occur in chains of bacteria, such as this streptococcus bacteria that causes some types of sore throats

15. STRUCTURE OF BACTERIA Structure Function Cell Wall
Protects and gives shape
Outer Membrane
Protects against antibodies (Gram Neg. Only)
Cell Membrane
Regulates movement of materials, contains enzymes important to cellular respiration
Cytoplasm
Contains DNA, ribosomes, essential compounds
Chromo-some
Carries genetic information
Plasmid
Contains some genes obtained through recomb.
Capsule & Slime Layer
Protects the cell and assist in attaching cell to other surfaces
Endospore
Protects cell agains harsh enviornments
Pilus
Assists the cell in attaching to other surfaces
Flagellum
Moves the cell

16. No Nucleus-DNA in Cytoplasm

17. Nutrition and Growth Temperature requirements
Heterotrophic or Autotrophic
Some are Photoautotrophs – Use sunlight for Energy
Some are Chemoautotrophs.
Many are Obligate Anaerobes.
Oxygen = Death
Ex. Clostridium tetani – Tetanus
Some are Faculatative Anaerobes
With or without Oxygen
Ex. Escherichia Coli
Some are Obligate Aerobes
Ex.) Mycobacterium tuberculosis
Temperature requirements
Some are Thermophilic, Some prefer acidic envmt.

18. Bacteria and Disease Disease Pathogen Areas affected
Mode of transmission
Botulism
Clostridium botulinum
Nerves
Improperly preserved food
Cholera
Vibrio cholerae
Intestine
Contaminated water
Dental Caries
Streptococcus mutans, sanguis, salivarius
Teeth
Environment to mouth
Gonorrhea
Neisseria gonorrhoeae
Urethra, fallopian
Sexual contact
Lyme disease
Berrelia burgdorferi
Skin, joints
Tick bite
Rocky Mountain SF
Rickettsia recketsii
Blood, skin
Salmonella
Contaminated food, water
Strep throat
Streptococcus pyogenes
URT, blood, skin
Sneezes, coughs, etc.
Tetanus
Costridium tetani
Contaminated wounds
Tuberculosis
Mycobacterium tuberculosis
Lung, bones
coughs

19. Some bacteria cause diseases --Disease causing bacteria are call
PATHOGENIC

20. Helicobacter pylori is the pathogenic bacteria that can causes ulcers

21. Leprosy is a bacterial infection that decreases blood flow to the extremities resulting in the deterioration of toes, ears, the nose and the fingers.

22. CHOLERA

23. LYME DISEASE

24. SALMONELLA

25. STREP THROAT

26. Common Antibiotics Antibiotic Mechanism Target bacteria Penicillin
Inhibits cell wall synthesis
Gram Positive
Ampicillin
Broad spectrum
Bacitracin
Gram Positive – Skin Ointment
Cephalosporin
Tetracycline
Inhibits Protein Synthesis
Streptomycin
Gram Neg. tuberculosis
Sulfa drug
Inhibits cell metabolism
Bacterial meningitis, UTI
Rifampin
Inhibits RNA synthesis
Gram Pos., some Neg.
Quinolines
Inhibits DNA Synthesis
UTI

27. Some Final Information
Because antibiotics have been overused, many diseases that were once easy to treat are becoming more difficult to treat.
Some Bacteria are Useful
Ex.) Producing and Processing food
Breaking down dead organic material
Make unripened cheese like ricotta and cottage by breaking down the protein in milk.

28. Non-living but depends on the living!
VIRUSES
Non-living but depends on the living!

29. STRUCTURE Nonliving Composed of Nucleic acid and protein
Cause many diseases
Virology – Study of Viruses
Comparison of Viruses and Cells below
Char. Of Life
Virus
Cell
Growth No
Yes
Homeostasis
Metabolism
Mutation
Nucleic acid
DNA or RNA
DNA
Reproduction
Only within host cell
Independently by cell division
Structure
Nucleic acid core, protein covering, some have envelope
Cytoplasm, cell membrane, etc..

30. Here is a non-enveloped bacteria virus inserting it’s DNA into a bacterial cell.

31. Characteristics of Viruses
2 essential features
1. Nucleic Acid
May be DNA or RNA
Helical, closed loop, or long strand
2. Protein Coat – called CAPSID
Some have ENVELOPE
Ex. Influenza, chickepox, herpes simplex, HIV
VIRAL SHAPE
Icosahedron – 20 triangular faces
Ex.) herpes, chickenpox, polio
Helix – Coiled spring
EX.)Rabies, measles, tobacco mosaic

32. All viruses have two main parts:
DNA or RNA – genetic info
Capsid – a protein encasement

33. Grouping Viruses Grouped according to:
Presence of Capsid and envelope – shape
RNA or DNA, single or double stranded – struct.
Viral Group
Nucleic Acid
Shape and Structure
Example
Papovaviruses
DNA
Icosahedral, non-env.
Warts, cancer
Adenoviruses
Resp. & intestinal infections
Herpesviruses
Icosahedral, enveloped
Herpes simplex, chicken pox, mono, shingles
Poxviruses
Complex brick, enveloped
Small pox, cow pox
Picornaviruses
RNA
Polio, hepatitis, cancer
Myxoviruses
Helical, enveloped
Influenza A, B, C
Rhabdoviruses
Rabies
Retroviruses
AIDS, cancer

34. Grouping Viruses
Viroids- The smallest known particle that can replicate.
Disrupt plant cell metabolism
Can destroy entire crops
Prions – Abnormal forms of proteins that clump together inside cells.
Clumping eventually kills the cell
Examples
Scrapie – in sheep
Mad Cow Disease

36. Viral Replication Picture
Click Movie to Play

37. Viruses and Human Disease
Control and Prevention of spread.
Vaccination & Antiviral drugs
Ex.) chickenpox vaccine, AZT, Acyclovir, protease inhibitors.
Emerging Viruses – exist in isolated habitats
Do not usually infect humans unless environmental conditions favor contact.
Several viruses are now linked to cancers such as leukemia, liver cancer, Burkitt’s lymphoma, cervical cancer.

42. PAPOVAVIRUSES
BACK

43. ADENOVIRUSES
BACK

44. HERPESVIRUSES
BACK

45. POXVIRUSES
BACK

46. After polio infections, the killer T-cell have destroyed the motor neurons that are producing the virus. The result is a loss of muscle control including the diaphragm. The iron lung changes the pressure to pump air in and out of the lungs.

47. Which US President had polio?