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) 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: feed on dead matter –Parasites: live on/in others Break down dead matter 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?

Salt, heat, & acid loving bacteria

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

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

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 because of thick capsule) –Gram positive: stains purple (easier to treat) Treatments differ depending upon results GRAM NEGATIVEGRAM POSITIVE

Gram Stain Overview

Eubacteria (Modern bacteria) Cyanobacteria: autotrophic bacteria Create oxygen for life on earth Created Earth’s ozone layer to block ultraviolet radiation (UV) from the sun –Oxygen (O2) is recombined into ozone (O3) in the stratosphere –Allows life to evolve on land

Helpful Bacteria In nature, bacteria return nutrients to the soil –Saprophytes: organisms that feed on dead material Bacteria have been engineered for human uses: –Food: cheese, bread, yogurt, cabbage, sauerkraut –Medicine: antibiotics –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.