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Bacteria Characteristics. Cell Structure. Prokaryote : no nucleus or organelles 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.
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Bacteria Characteristics
Cell Structure • Prokaryote: no nucleus or organelles • 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 Bacterial Shapes
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 Bacteria Reproduction
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 Aerobe = must live in oxygen • Obligate Anaerobe = cannot live in oxygen • Facultative Aerobe = can live with or without oxygen The bacteria that causes TB lives in your lungs… which type is it?
GRAM NEGATIVE GRAM POSITIVE 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
UV Bacteria UV 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 Ozone layer (O3) develops over millions of years Uninhabited land Cyanobacteria in Ocean water O2 O2 O2 O2
Helpful in nature Cyanobacteria: create O2 Decomposers: recycle C Nitrogen fixer bacteria Bacteria have been engineered for human uses: Food: cheese, bread, yogurt, cabbage, sauerkraut Medicine: antibiotics Industry: insecticides, fuel, environmental cleanup Helpful Bacteria
Kingdom Bacteria • Gram Positive • Thinner capsule • Stains purple • Gram Negative • Thicker capsule • Stains pink • Cyanobacteria • Autotrophs • Created ozone layer
Brush, Floss, & Rinse Your Teeth! GINGIVITIS HEALTHY MODERATE PERIODONTITIS ADVANCED PERIODONTITIS
Most bacteria killed Strong Survive Resistant Bacteria Only Strong Reproduce
Kingdoms Archaea Salt, heat, & acid loving prokaryotes
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 archaea • 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
Kingdom Archaea • Halophiles • thrive in salty environments • Methanogens • live in anaerobic environments • produce methane as waste • Thermophiles • thrive in extremely hot environments
Name this bacteria shape! Bacillus
Name the process shown in this animation. Binary Fission
1) What is the main difference between bacteria and all other life on Earth? 2) What is the purpose of… ribosomes? pili? endospores? capsule? 3) Name the process where bacteria divide themselves? 4) Examine the next slide and identify the cell parts. 5) How do the 3 types of respiration differ among bacteria? 6) Which archaebacteria love salt? 7) How do Gram + and – bacteria differ? 8) Which beneficial gas do cyanobacteria release into the atmosphere? 9) What did this gas eventually create? Review