Archaebacteria and Eubacteria Prokaryotes Archaebacteria and Eubacteria

They are Everywhere Very cold, hot, salty, acidic environments They exist in our digestive systems, and in our mouths They also help to recycle carbon and other important nutrients in the soil

2 branches of Monera Bacteria and Archaea Archaea – extremophiles – they live in very extreme conditions Thermophiles – live in very hot conditions Halophiles – live in very salty conditions Methanogens – archaea bacteria that live in anaerobic conditions and produce methane gas

Pili on bacteria

Shapes of Bacteria Bacilli – rod shaped bacteria Coccus – round bacteria (strep/staph) Spirochetes – spiral-shaped bacteria (ex. Syphilis) Clostridium botulinum – causes botulism – produces endospores that can remain dormant for years

Shapes

Endospores - Anthrax

Bacterial Reproduction Bacteria reproduce by binary fission Binary fission - when the bacteria continuously copy their DNA and divide rapidly. Conjugation – the exchange of genetic material between two bacterial cells

Conjugation

Bacterial Nutrition Photoautotrophs – bacteria that photosynthesize – ex. Cyanobacteria Chemoautotrophs – make food from CO2 and other chemicals Chemoheterotrophs – obtain food from an organic source

Cyanobacteria

Bacterial Pneumonia

Lyme Disease

Lyme Disease

Bacteria that cause disease Bacteria and other microorganisms that cause disease are called pathogens. Some bacteria produce exotoxins. Exotoxins are poisons that are very harmful. Ex. Staphylococcus aureus produces a flesh eating exotoxin. Endotoxins are found in the bacterial cell membrane Ex. Salmonella has an endotoxin in its cell membrane that causes food poisoning

Bacteria and chemical recycling Bacteria recycle nitrogen and carbon in the soil. Bacteria decompose dead and decaying matter and return vital nutrients to the soil.

Bioremediation Bioremediation – the use of bacteria decomposers to treat our sewage Bacteria are also used to clean oil spills

Gram positive and negative Gram staining is a way to determine the type of bacterial infection present. The cell wall determines whether it is a gram positive or negative bacteria.

Gram Staining

Other facts about bacteria Live with other things in symbiotic relationships Ex. Cows do not digest cellulose, but feed on grass. They have bacteria in their guts to break down the cellulose. This is a mutualistic relationship Mutualism - when both organisms benefit from the relationship. Bacteria can also use flagella to move