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• Get out Classification Booklet– We are going to grade “Class shows

closeness”

• Reminder: Quiz next Tuesday February 3rd

BACTERIA

I. Kingdom Eubacteria (True Bacteria)Bacteria are located everywhere – air, water,

land, on and in living organisms, including people.

A. General Characteristics: 1. All are unicellular

2. All are prokaryotic (no nucleus) 3. Can live in both aerobic (with O2) and anaerobic (without O2) environments

pili (attachment)

cytoplasm

cell membrane (inner)

ribosomes

genetic material

flagella (movement)

cell wall (outer)

B. Example

Cell Membrane

Cell Wall

Genetic Materia

l

Flagella

Cytoplasm

Example: E. coli

Bacteria are much larger in size than viruses, but smaller than cells.

C. Cell Wall – all bacteria have cell walls composed of peptidoglycan protein

+ -

1. Gram staining determines the type of cell wall

Gram + Purple/violet

Gram - Red, more complex cell wall

Gram-positive Staph aureus at the top

Gram-negative Pseudomonas aeruginosa at the bottom.

How do antibiotics work? 2. Antibiotic used to cure bacterial infection depends on: Gram + or Gram –

3. Antibiotics work by disrupting the formation of the peptidoglycan cell wall.

4. Gram – bacteria are harder to treat due to complexity of cell wall.

D. Causes disease:

1. destroys cells – of infected organisms by breaking them down for food 2. releases toxins – that travel

throughout the body interfering with normal activity of the host Scanning electron

microscopy image of bacteria (the cylindrical objects) attached to host cells. These bacteria are in the process of injecting the host cells with the toxins. (Credit: Hebrew University illustration)

E. Three Shapes

1. cocci – round staphlo - cluster

2. bacilli – rod

strepto - chain

3. spirilla – spiral

Coccus(Sphere-shaped)

Ex: Streptococcus

Bacilli(rod-shaped)

Ex: Lactobacillus

Spirillum(Spiral-shaped)

Ex: Spirillum

coccus bacillus spirillum

coccusspirillum

bacillus

What shape?

F. Survival

1. tough outer coat forms around DNA and cytoplasm of some bacteria –

endospore

can survive a long time and in harsh conditions ex: tetanus in soil

G. Importance:

1. Beneficial a. breakdown and obtain energy

from dead materials -- decomposers

Example: Compost piles need microorganisms (ex. bacteria) to decompose (breakdown) matter.

b. dairy industry - bacteria in 2:08 minute

video

yogurt, sour cream and cheese

From Sourdough to Swiss Cheese: Bacteria in Food

c. Oil spills – digest petroleum, can clean up small oil spills

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• Get out Classification packet – We are going to check homework

• Reminder: Quiz next Tuesday February 3rd

d. Genetic engineering—

Recombinant DNA – insert human genes

into bacteria plasmid

Ex: bacteria produce human

insulin for diabetes

e. relationship between two different organisms-- symbiosis relationship where both organisms benefit--

mutualism

example: E. coli in intestines helps us digest food and make vitamins. 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.)

3:07 minute videoInfectious Diseases Caused by Bacteria

2. Harmful :a. diseases –

pneumonia, strep throat, tuberculosis, tooth decay, bad breath, syphilis, anthrax, tetanus, Lyme disease, staph, bacterial meningitis, botulism

Tetanus

Strep Throat

Anthrax

3:15 minute videoAntibiotics

b. food spoilage and poisoning – caused by Salmonella and Staphylococcus (handout)

c. antibiotics fight bacterial infections, but often have – digestive side effects

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.

Geyser

II. Kingdom Archaebacteria a. First known prokaryotes-

Archaebacteria (archae=ancient)

b. Live in very harsh environments – • Halophiles: “salt loving”, use osmotic

pressure and chemical substances to help control the amount of salt inside the cell.

Located The Great Salt Lake, Dead Sea, evaporation ponds.

• Thermophiles: contain adaptations that allow them to live in areas of high temperature (113-252 °F).

Located Yellowstone National Park, deep sea hydrothermal vents

Salt Lake City

Hydrothermal vents

3:12 minute video

Industrial Uses for Bacteria

• Methanogen bacteria: Live in intestines of animals, especially cows and other grazing animals –

• They convert C and H into

methane (CH4) gas which reacts with O2 to produce CO2, which affects our – atmosphere by producing CO2 for photosynthesis

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• Get out Classification Booklet – We are doing the Virus/Bacteria Station

Lab today

• Reminder: Quiz tomorrow over Classification and Bacteria Notes

• Tutorials will be offered after school with Ms. Tran or tomorrow during enrichment