Bacteria Characteristics

Cell Structure 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

Bacterial Shapes Many bacteria grow in colonies 3 Basic Shapes: 1) Bacilli = 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

Nutrition Heterotrophs: feed on matter produced by others Saprophytes: absorb nutrients from dead matter Parasites: absorb nutrients from living matter Essential to healthy ecosystems

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

Salt, heat, & acid loving bacteria 2 Bacterial Kingdoms Salt, heat, & acid loving bacteria

Archaea Live in extreme environments 1) Methanogens: Anaerobic Produce methane gas as a waste product Habitat: Swamps, sewage, digestive tract

Archaea 2) Thermophiles Heat and acid loving bacteria Habitat: Deep sea vents, volcanoes, hot springs (230°F)

Archaea 3) Halophiles Thrive in areas of high salt concentration Salt normally dehydrates organisms Use salt to make energy

Eubacteria (Modern Bacteria) Common to most environments on Earth Identified by Gram Stain test Gram negative: stains pink harder to treat Gram positive: stains purple easier to treat Treatments differ depending upon results

Gram Stain Overview

Eubacteria (Modern bacteria) UV UV UV UV Cyanobacteria: autotrophic bacteria Evolutionary Importance Early life lived in oceans (no ozone layer) Cyanobacteria released O2 into the atmosphere O2 recombined into ozone (O3) in the stratosphere Protective layer allowed life to evolve on land UV UV Ozone layer (O3) develops over millions of years Uninhabited land Cyanobacteria in Ocean water O2 O2 O2 O2

Helpful Bacteria Helpful in nature Cyanobacteria: create O2 Decomposers: recycle C Nitrogen fixer bacteria Bacteria have been engineered for human uses: Food: cheese, bread, yogurt, sauerkraut Medicine: antibiotics Industry: insecticides, fuel, environmental cleanup

Brush, Floss, & Rinse Your Teeth! GINGIVITIS HEALTHY MODERATE PERIODONTITIS ADVANCED PERIODONTITIS

Resistant Bacteria Only Most bacteria killed Strong Survive Resistant Bacteria Only Strong Reproduce

Name this bacteria shape! Cocci

Name this bacteria shape! Bacillus

Name these cell parts! Pili

Name the process shown in this animation. Binary Fission