Chapter 17 Cont prokary & protists

Chapter 17 Cont prokary & protists - Chapter 17...

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Unformatted text preview: Chapter 17 Cont. Chapter Prokaryotes & Protists Today we will Today Discuss prokaryotes: – The domains Bacteria The & Archaea Archaea Discuss eukaryotes in Discuss the Domain Eukarya, Kingdom Protista Kingdom 3 domains kingdoms Bacteria ? prokaryotes Archaea Eukarya ? Protista Fungi eukaryotes Plants Animals DNA/RNA show DNA/RNA Bacteria: 13-15 Kingdoms Bacteria: maybe more more Archaea: 3 Kingdoms kingdoms Bacteria ? prokaryotes Eukarya ? Single celled Archaea Protista eukaryotes Plants Animals multicelled Fungi Prokaryotes 3.5 billion year old prokaryote fossil almost They are everywhere They Outnumber all eukaryotes More in your mouth than all More people who ever lived people Brush bristles ba cte ria Bacteria on pin head mouth Prokaryotes Life starts 2 domains 1. Bacteria 2. Archaea • Most are extremophiles • Halophiles • Thermoacidophiles • Methanogens 3.5 billion year old Prokaryote fossil Prokaryote characteristics Single celled ??? Lack organelles ribosomes No ‘true’ nucleus no outer membrane just a coiled loop of DNA @ 50% have flagellum Most have cell walls Key difference: bacteria vs archeae Key Plasma membrane – Archaea have unusual lipids permitting high Archaea temps temps Archaea have diverse wall types No peptidoglycan Some have walls mainly of polysaccharides Some have walls of pure protein Some have no cell walls Classified by Classified Shape Means of locomotion Pigments Nutrient requirements Appearance of colonies Staining properties – Gram positive/negative Cell walls Cell Bacteria shapes Bacteria cocci bacilli spirochetes 3 basic – Coccus (spherical) Coccus (spherical) staphylococci Streptococci Sore throats – Bacillus (rod) Bacillus (rod) Decomposers Antibiotics – Spirochetes (spiral or Spirochetes corkscrew) corkscrew) Syphilis & Lyme disease Bacteria shapes Bacteria Info only Bacterial shape diversity Bacterial heterocysts Can form colonies Endospore A cell within a cell Function: survivabilit y Endospore Normally dehydrated Does not metabolize Survives Heat & cold Lack of water Lack of nutrients Most poisons Botulism Anthrax Prokaryote flagella = locomotion Prokaryote @ 50% Has a “motor” which Has rotates the flagella rotates – – – Like a propeller Fwd: counterclockwise Bwd: clockwise One at either end Or A tuft at one end Flagellum Permit: Or scattered all over • Movement to new habitats • Migration to nutrients • Leaving bad environments Prokaryotes reproduce by Prokaryotes Binary fission – A form of asexual repro – Produces genetically exact Produces copies (clone) copies Prokaryotes reproduce by Prokaryotes Binary fission – A form of asexual repro – Produces genetically exact copies – Rapid: once every 20 Rapid: minutes (1021/day = minutes /day sextillion) sextillion) Exploits temporary Exploits habitats habitats Permits fast evolution Permits therefore increased chance of survival chance Other Conjugation Conjugation – Passes DNA via sex pili between same or Passes closely related bacterial species closely Transformation – Enveloping of free DNA Transduction – Movement of bacterial DNA via Movement bacteriophages from one cell to another bacteriophages plasmids The Nutritional Diversity of Prokaryotes The They “invented” every type of nutrition we They observe throughout life observe How energy and carbon are obtained to make organic compounds The Nutritional Diversity of Prokaryotes The They “invented” every type of nutrition we observe throughout life Definitions – Autotroph The Nutritional Diversity of Prokaryotes The They “invented” every type of nutrition we observe throughout life Definitions – Autotroph: Autotroph: –Heterotroph: classifications Heterotroph: classifications The Nutritional Diversity of Prokaryotes The They “invented” every type of nutrition we observe throughout life Definitions – Autotroph: makes own food from either sun or chem energy – Heterotroph: gets energy from an Heterotroph: sugar organic compound organic Nutritional classifications of organisms Nutritional Photoautotrophs Photoautotrophs Chemoautotrophs Photoheterotrophs Photoheterotrophs Chemoheterotrophs Chemoheterotrophs Bacteria help Bacteria In digesting cellulose To produce cheeses, yogurts, sauerkraut In us, make vitamins K and B12 Are nature’s recyclers – bioremediation Vaginal bacteria – pH 4.0-4.5 Nitrogen-fixing bacteria Prokaryotes can be bad bad Pathogenic Bacteria (disease producing) – Most synthesize toxic substances that cause Most disease symptoms disease Prokaryotes can be bad bad Pathogenic Bacteria (disease producing) – Most synthesize toxic substances that cause disease symptoms 2 types – Exotoxins: Are poisons secreted by bacterial Exotoxins: cells cells Tetanus & botulism attack nerve tissue Staphylococcus aurenus (flesh eating) – Endotoxins: Chemical components of cell walls Salmonella (food poisoning) & typhoid fever food Prokaryotes can be bad bad Pathogenic Bacteria (disease producing) – Most synthesize toxic substances that cause disease symptoms 2 types – Exotoxins: Are poisons secreted by bacterial cells Tetanus & botulism attack nerve tissue Staphylococcus aurenus (flesh eating) – Endotoxins: Chemical components of cell walls Salmonella (food poisoning) & typhoid fever food Defenses Defenses – Sanitation – Antibiotics – Education Education Kingdom Protista “the protists” “the Not a fungus nor a plant and also not an animal Protists Belong to Domain Eukarya Domain Are the ‘first’ eukaryotes – Single and multi-cellular Single – and also form colonies Eukaryote characteristics Eukaryote Have Have organelles organelles Have true nucleus nucleus Have strand Have DNA DNA Eukaryote characteristics Eukaryote Formed organelles Via endomembrane system system or or Via endosymbiosis & endocytosis endocytosis Protist Reproduction Protist Reproduction Reproduction – mostly via asexual mitotic cell mostly division (clone) division – Some sexual repro But an embryo is never formed – Can also exchange genetic Can material via cytoplasmic bridge cytoplasmic Protists nutrition classes Protists Via 3 modes of nutrition Photosynthesis (photoautotrophy) Photosynthesis Ingestion (chemoheterotrophy) Ingestion Absorption (chemoheterotrophy) Absorption How Protists classified How Traditionally into 4 categories Protozoans Slime molds Unicellular algae Seaweed Above grouped according to physical similarity but genetic DNA comparisons changing all genetic BI G TI M E DNA evolutionary breakout of protist ps ou gr 4 ws pp ne su g kin a ata Bre ic d et en wg Ne ts 1 or 4 major categories major – Protozoans – Slime molds – Unicellular algae – Seaweed Seaweed Protozoans Protozoans 4 “groups” Flagellates •Move by one or more flagellum •Typanosome - Tsetse fly & african sleeping sickness Typanosome Tsetse Protozoans Protozoans 4 “groups” Flagellates •Move by one or more flagellum •Typanosome - Tsetse fly & african sleeping sickness Typanosome Tsetse Ciliates Ciliates •Move and feed via cilia •Paramecium Protozoans Protozoans 4 “groups” Flagellates •Move by one or more flagellates •Typanosome - Tsetse fly & african sleeping sickness Typanosome Tsetse Ciliates Ciliates •Move and feed via cilia •Paramecium Apicomplexans •Parasites that enter host’s Parasites RBCs via “apex mechanism” RBCs •Malaria & Plasmodium Malaria organism organism Protozoans Protozoans 4 “groups” Flagellates •Move by one or more flagellates •Typanosome - Tsetse fly & african sleeping sickness Typanosome Tsetse Ciliates Ciliates •Move and feed via cilia •Paramecium Apicomplexans Apicomplexans •Parasites that enter host’s RBCs via apex mechanism •Malaria & Plasmodium organism Malaria organism Amoebas •Move and feed by pseudopodia Slime molds Slime Decomposers – 2 types 1 Plasmodial slime mold slime •Single cell Single w/many nuclei nuclei 2 Cellular slime mold • Single cell to slug like colony •Studied extensively to see Studied how multicellular organisms evolved evolved Unicellular algae algae Are photosynthetic 3 groups Dinoflagellates • cell plates of cellulose cell • cause of red tides red Unicellular algae algae Are photosynthetic 3 groups Dinoflagellates • cell plates of cellulose cell • cause of red tides red Diatoms Has glassy (silicate) cell walls Uses nutrients stored as oil to float Unicellular algae algae Are photosynthetic 3 groups Dinoflagellates • cell plates of cellulose cell • cause of red tides red D & D form plankton aka phytoplankton = Communities of organisms that swim or drift near surface of water bodies. They are the bottom of sea food chain Saving us from CO2 and massive global warming Diatoms Has glassy (silicate) cell walls Uses nutrients stored as oil to float Unicellular algae algae Are photosynthetic 3 groups Dinoflagellates • cell plates of cellulose cell • cause of red tides red D & D form plankton aka phytoplankton form plankton phytoplankton =Communities of organisms that swim or drift near surface =Communities of water bodies. They are the bottom of sea food chain of Diatoms Has glassy (silicate) cell walls Uses nutrients stored as oil to float Green algae Most closely related to plants Single celled with 2 flagella Single but has a Volvox colony form colony ancestor Seaweeds (algae) Photosynthetic, large, multicellular multicellular Plantlike but not ancestors ????? – Thallus Holdfast, stipe, blade 3 types – Red, brown (kelp), green, golden – Found on rocky shores/just off-shore Some edible Agar, a gel derived from seaweed cell walls Agar, – – – forms base for culture mediums Helps puddings set An ingredient in lipstick An Amen!!! ...
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This note was uploaded on 06/02/2011 for the course BIOL 110 taught by Professor Duwel during the Fall '08 term at South Carolina.

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