Bacteria & Archaea • 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” that forms around DNA to protect in harsh times • Many bacteria grow in • 1) Bacilli/Bacillus = Rod colonies • 2) Cocci/Coccus = Spherical • 3 Basic Shapes: • 3) Spirilla/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 The bacteria that causes TB lives in your lungs… which type is it? • Obligate Aerobe = must live in oxygen • Obligate Anaerobe = cannot live in oxygen • Facultative Aerobe = can live with or without oxygen UV UV UV UV UV UV Bacteria • 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 Cyanobacteria in Ocean water Uninhabited land 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 Identifying Bacteria • 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 NEGATIVE GRAM POSITIVE Gram Stain Overview Kingdom Bacteria Gram Positive Gram Negative • Thinner capsule • Stains purple • Thicker capsule • Stains pink Cyanobacteria • Autotrophs • Created ozone layer HEALTHY MODERATE PERIODONTITIS GINGIVITIS ADVANCED PERIODONTITIS Salt, heat, & acid loving prokaryotes • Live in extreme environments • 1) Methanogens: – Anaerobic (Obligate Anaerobe) – Produce methane gas as a waste product – Habitat: Swamps, sewage, digestive tract 2) Thermophiles • Heat and acid loving archaea • 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 Kingdom Archaea Methanogens Halophiles • thrive in salty environments Thermophiles • live in anaerobic environments • produce methane as waste • thrive in extremely hot environments Silly…yet educational…Archaea AKA Archaebacteria Name this bacteria shape! Name this bacteria shape! Name these cell parts! Name the process shown in this animation. 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?