1

2 TYPES OF BACTERIA:

Bacteria - Get food from an outside source

Cyanobacteria - Make their own food

Bacteria - small one celled monerans

Bacteria 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 process

2) 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. Disinfectants

Antiseptic- 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