1

2 TYPES OF BACTERIA:Bacteria - Get food from an outside sourceCyanobacteria - Make their own foodBacteria - small one celled moneransBacteria like a warm, dark, and moist environment

They are found almost everywhere:-water -air-soil -food-skin -inside the body-on most objects

2

Spiralspirilla

Rod-Shaped bacilli, bacillus

Roundcocci

3 Shapes of Bacteria

Bacteria are classified by shape into 3 groups:

3

3 Shapes of BacteriaBacillus anthracis –

(bacillus) – causes the disease anthrax in livestock (cows)Neisseria meningitidis (coccus) – causes meningitis, a life threatening disease where the brain becomes inflammed

Leptospira interrogans – (spirilla)

4

• Binary Fission - the process of one organism dividing into two organisms

• Fission is a type of asexual reproduction

Reproduction of Bacteria

• Asexual reproduction- reproduction of a living thing from only one parent

5

• The time of reproduction depends on how desirable the conditions are

• Bacteria can rapidly reproduce themselves in warm, dark, and moist conditions

• Some can reproduce every 20 minutes

(one bacteria could be an ancestor to one million bacteria in six hours)

Reproduction of Bacteria

6

Bacteria Survival Endospore -a thick celled structure that forms inside the cell• they are the major cause of food poisoning• they can withstand boiling, freezing, and extremely dry conditions• it encloses all the nuclear materials

and some cytoplasm

• allows the bacteria to survive for many years

7

Controlling Bacteria3 ways to control

bacteria:1) Canning - the process of sealing food in airtight cans or jars after killing bacteria

* endospores are killed during this process2) Pasteurization - process of heating milk to kill harmful bacteria

3) Dehydrating-removing water from food * Bacteria can’t grow when H2O is removed

example: uncooked noodles & cold cereal

8

Harmful Bacteria

Pathogenic bacteria – bacteria which cause disease. Enter a body and take nutrients from the host or produce toxins

- Lyme disease - cholera- bubonic plague - Tuberculosis- salmonella

Communicable Disease – Disease passed from one organism to another

9

Helpful Bacteria• Decomposers help recycle nutrients into

the soil for other organisms to grow• Bacteria grow in the stomach of a cow to break down grass and hay

• Many are used to make antibiotics that can treat bacterial diseases• Some bacteria help make insulin that help people with diabetes

• Used to make industrial chemicals

10

• Used to treat sewage           Organic waste is consumed by the bacteria,

used as nutrients by the bacteria, and is no longer present to produce odors, sludge, pollution, or unsightly mess.

• foods like yogurt, cottage & Swiss cheese, sour cream, buttermilk are made from bacteria that grows in

milk

Helpful Bacteria

11

Controlling BacteriaAntiseptic vs. DisinfectantsAntiseptic- chemicals that kill

bacteria on living things• means – “against infection”Examples: iodine, hydrogen peroxide, alcohol, soap, mouthwash

Disinfectants - stronger chemicals that destroy bacteria on objects or nonliving things

12

BLUE-GREEN BACTERIA

Blooms- occur when the bacteria multiplies in great numbers and form scum on the top of the water

can be toxic to humans and animals