Bacteria

Bacteria Smallest and simplest organisms on the planet Also the most abundant 1 gram of soil has over 2.5 billion bacteria

Bacteria Prokaryotes – single celled, no nucleus around their genetic material Belong to either the Archaebacteria or Eubacteria kingdoms

General Characteristics: The Bacteria Cell Bacteria are located everywhere – air, water, land, and living organisms including people. General Characteristics: 1. All are unicellular (one-celled structural level) 2. All are prokaryotic - cells that lack nucleus (no nuclear envelope) (PRO = NO nucleus) 3. All have cell walls – NO cellulose in cell walls

Example: E. coli Cytoplasm Genetic Material Cell Wall Cell Membrane Flagella Example: E. coli

5. Bacteria are much larger in size than viruses.

6. Bacteria usually have one of three different cell shapes: Coccus (Sphere-shaped) Ex: Streptococcus Bacilli (rod-shaped) Ex: Lactobacillus Spirillum (Spiral-shaped) Ex: Spirillium

What shape? bacillus spirillum coccus spirillum coccus bacillus

How do bacteria eat? Photosynthetic bacteria Some make their own food from sunlight (autotrophic) Some are scavengers Consume other organisms or their food (heterotrophic) Example: The bacteria in your stomach are now eating what you ate for breakfast Some are warriors (pathogens) They attack other living things Example: The bacteria on your face can attack skin causing infection and acne Harmless bacteria on the stomach lining E. Coli O157:H7 is a pathogen USDA NIFSI Food Safety in the Classroom© University of Tennessee, Knoxville 2006

Bacterial Reproduction Asexual Reproduction Binary Fission Generation Time (Doubling Time) time required for a cell to divide most about 1 Hr. To 3 Hrs. E. coli - 20 minutes Mycobacterium tuberculosis - 24 Hrs.

Binary Fission - unchecked E. coli - generation time of 20 min. 20 generations (about 7 hrs.) 1 million cells 30 generations ( about 10 hrs.) 1 billion cells 72 generations ( about 24 hrs.) 1 x 1021 1,000,000,000,000,000,000,000 cells

Endospore Formation If the conditions are unfavorable, some species form a thick, protective membrane Once the membrane is formed the bacteria is known as an endospore Can survive in outer space on meteors! Is that how life started on our planet???

The Role of Bacteria in Nature All Bad??? Diseases?? Diseases Infections Epidemics Food Spoilage Only 1% of all known bacteria cause human diseases About 4% of all known bacteria cause plant diseases 95% of known bacteria are non-pathogens

Bacterial Benefits Humans Oxygen Production (Autotrophic Bacteria created our atmosphere) Environmental Cleanup - recycle nutrients back into the environment (sewage treatment plants)

D. Importance: 1. Beneficial a. breakdown dead matter to recycle nutrients into ecosystem - decomposers

c. Oil spills - bacteria can digest small oil spills

Recombinant/synthetic DNA (Ex: Insulin) d. Genetic engineering— Recombinant/synthetic DNA (Ex: Insulin)

intestines-both organisms benefit e. symbiotic relationship - E. coli and our intestines-both organisms benefit Example: E. coli in intestines helps us digest food and make vitamins (such as Vitamin K and B-complex) In return, human intestines provide food and shelter for bacteria. (This strain of E. coli is different from the E. coli strain that causes food poisoning.)

They produce various food products cheese, pickles, sauerkraut, green olives yogurt, soy sauce, vinegar, bread

Causes Disease by: 1. Destroying cells of infected organisms by breaking the cells down for food.

Releases toxins (poisons) which destroy cells of infected organism. Must have access to new hosts to spread.

Anthrax Tetanus Strep Throat Harmful : human diseases – strep throat, tuberculosis, tooth decay and bad breath, anthrax, plague, tetanus, food poisoning Strep Throat Tetanus

b. food spoilage and poisoning – caused by Salmonella and Staphylococcus c. Treated with antibiotics – Some bacteria are able to survive in presence of antibiotics that kill other bacteria – antibiotic resistant bacteria Note: This is why doctors tell you to take the entire amount of medicine given even if you start to feel better because if not, bacteria will have the chance to evolve and become antibiotic resistant.

Good Guy/Bad Guy Poster Project Objectives: Create a poster of either good or bad bacteria Identify the name/type of bacteria, where it is found, how it is transmitted, how does it hurt or help us, how is it killed or allowed to thrive Make it educational & entertaining! 

Things to include for your bad guy wanted poster: Name of organism (common and scientific) Drawing/picture with characteristics labeled and description of the organism Where is it found? How is it transmitted? Is it infectious? Who is targeted? How does it cause harm? What are symptoms? Have there been major outbreaks? How can it be treated/eliminated?

Choose a Bad Guy: *+Pneumonia *Whooping Cough *E. coli *Botulism *Typhoid Fever +Measles *Cholera *Scarlet Fever +Mumps *Tuberculosis +Herpes 1 +Herpes 2 *+Meningitis *Tetanus +RSV *Strep Throat *Lyme Disease +AIDS *Black Plague *Gangrene *Flesh Eating

Things to include for your good guy personal ad: Name of organism (common and scientific) Who/what does it benefit? What is it used for? Explain the relationship Include a drawing/picture with labeled characteristics Where is it found? What are its needs?