Prokaryote: no nucleus –Chromosome & plasmids float freely in cytoplasm Ribosomes: create proteins Flagella: used in movement Pili: act as anchors Capsule: outer coating Endospore: “cocoon” to protect DNA in harsh times

Many bacteria grow in colonies 3 Basic Shapes: 1) Bacillus = Rod 2) Coccus = Spherical 3) Spirillum = Spiral

Bacteria Reproduction Binary Fission: asexual reproduction where one cell splits into two cells –Both cells have identical sets of DNA –Less genetic diversity Conjugation: process where DNA is exchanged –Cells connect by pili –DNA exchanged Creates genetic diversity Click pic

Nutrition Many Heterotrophs –Feed on living and dead matter & return nutrients to soil Some autotrophs –Cyanobacteria… Essential to healthy ecosystems

Obligate Anaerobic = cannot live in oxygen Facultative aerobic = can live with or without oxygen Obligate Aerobic = must live in oxygen The bacteria that causes TB lives in your lungs…which type is it?

Kingdoms of Bacteria

Live in extreme environments Offer glimpse of early earth 3 Main Categories: –1) Methanogens: methane producing –2) Halophiles: thrive in salty environments –3) Thermophiles: thrive in extreme heat (~230°F)

Kingdom Eubacteria Modern Bacteria Often identified by Gram Stain test –Gram negative: stains pink harder to treat because of extra outer layer –Gram positive: stains purple Treatments differ depending upon results

Gram + Gram -

Gram Stain Overview

3.5 billion years ago!!!

Cyanobacteria are some of oldest living organisms on the planet!Cyanobacteria are some of oldest living organisms on the planet!

O2 Autotrophs: create O 2 during photosynthesis Evolutionary Importance –Early life lived in oceans (no ozone layer) –Cyanobacteria released O 2 into the atmosphere –Oxygen recombined into ozone in the stratosphere –Protective layer allowed life to evolve on land UV Ocean water Cyanobacteria O2 Ozone layer (O 3 ) develops over millions of years Uninhabited land UV

Helpful Bacteria Bacteria have been engineered for human uses: –Food: cheese, bread, yogurt, cabbage, sauerkraut –Medicine: antibiotics, insulin –Industry: insecticides, fuel, environmental cleanup

HEALTHY GINGIVITIS MODERATE PERIODONTITISADVANCED PERIODONTITIS

Name this bacteria shape!

Name these cell parts!

Name the process shown in this animation.