Kingdom Monera - SD41blogs.ca

Kingdom MoneraThese notes are to help you check youranswers in your Bacteria unit handoutpackage that you received in class.

Textbook reference pages Textbook Section 17-2 & 17-3 pages 360-375

Basic structures of bacteria (page 2) Refer to diagram on text page 361 Nucleoid – region where bacterial DNA(genetic material) is located Ribosomes - organelles for making proteins inthe cell

Basic structures of bacteria Cell wall – tough outer thicker layer; givesbacteria their shape Cell membrane – thin layer just inside the cellwall; regulates substances in and out of thecell Capsule – layer of slime surrounding the cellwall; allows the bacteria to stick to surfacesand resist host defences

Basic structures of bacteria Flagella – long whip-like organelle formovement

Another way for prokaryotes to adhere to oneanother or to the substratum is by surfaceappendages called pili.– Pili can fasten pathogenic bacteria to the mucousmembranes of its host.– Some pili arespecialized forholding twoprokaryote cellstogether longenough to transferDNA duringconjugation.Fig. 27.6Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Identifying Monerans(page 1) Monerans can be identified by1. Cell shape2. Cell arrangement3. Cell wall4. Motility or how bacteria move

Bacteria Cell Shapes

Cell Shape and Arrangement Coccus / cocci – sphericalshaped;Example: pneumonia Bacillus / bacilli – rodshapedExample:tuberculosis Spirillum / spirilla – spiralor coil shapedExample: Syphilis

Cell ShapeShapeDescriptionDrawingEampleCoccus (singular) / sphericalcocci (plural)shapedPneumoniaBacillus /bacillirodshapedTuberculosisSpirillum /spirillaspiral orcoilshapedSyphilis

Cell Shape and Arrangement

Cell arrangement(page 3) Single cellDiplo – pairsStrepto - chainsStaphylo – clusters What do the following names might mean? Streptococcus Lactobacillus

Cell WallGram-positiveStain: Crystal VioletColor: purpleCell wall type: thick layer of carbohydratesand proteins outside the cell membraneGram-negativeStain: safraninColor: red / pinkCell wall type: a second layer ofcarbohydrates and lipids (fats) molecules

An update on the phylum classification Classification is a human construct for organizing information aboutorganisms and it over time as new discoveries are made. In the pastKingdom Monera contained the phylums Archaebacteria and Eubacteria. However due to new discoveries in biochemistry, DNA, etc. these phylumshave been rearranged and a new level has been created above theKingdom taxa called Domain. Kingdom Monera does not exist now and has been replace by DomainArchaea and Domain Bacteria with Kingdoms underneath these large taxagroups. (Domain Eukarya contains the other 4 kingdoms: Protista, Plantae, Fungi,& Animalia) However it’s still useful to refer to the terms archaebacteria,methanogens, halophiles, thermophiles, eubacteria, cyanobacteria andprochlorobacteria because these terms describe bacteria with similarcharacteristics. (page 4)

Prokarytes are wherever there is life and theythrive in habitats that are too cold, too hot,too salty, too acidic, or too alkaline for anyeukaryote. The vivid reds,oranges, andyellows thatpaint theserocks arecolonies ofprokaryotes.Fig. 27.1Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Bacteria and archaea are the two mainbranches of prokaryote evolution Molecular evidence accumulated over the lasttwo decades has lead to the conclusion thatthere are two major branches of prokaryoteevolution, not a single kingdom as in the fivekingdom system. These two branches are the bacteria and thearchaea.– The archaea inhabit extreme environments anddiffer from bacteria in many key structural,biochemical, and physiological characteristics.Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Current taxonomy recognizes two prokaryoticdomains: domain Bacteria and domainArchaea.– A domain is a taxonomic level above kingdom.– The rationale for this decision is that bacteria andarchaea diverged so early in life and are sofundamentally different.– At the same time, theyboth are structurallyorganized at theprokaryotic level.Fig. 27.2Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Obtaining Energy(page 5)a) phototrophic autotrophs – capture energy ofsunlight and produce their own food;(similar to green plants)b) chemotrophic autotrophs – obtain energyfrom inorganic molecules such as hydrogensulfide, nitrites, sulfur, iron(refer to textbook page 365)

c) chemotrophic heterotrophs – obtain energy by takingorganic molecules and then breaking them down andabsorbing them (includes most bacteria and animals)d) phototrophic heterotrophs – photosynthetic (use sunlightfor energy) but also need organic compounds fornutritionStudy tip: “autotroph” refers to organisms that can maketheir own food, whereas “heterotroph” refers to organismsthat need to consume other organisms (dead or alive) fornutrients; “photo” means light;

Bacterial respiration Respiration is the process that requiresoxygen and breaks down food molecules torelease energy. Fermentation is another process but it isdifferent from respiration in that it does notrequire oxygen to carry out energyproduction

Bacterial respiration Obligate aerobes: need constant supply ofoxygen Obligate anaerobes: must live in the absence ofoxygen; will die if oxygen is present; example:intestinal bacteria Facultative anaerobes: will use oxygen ifpresent but can also use fermentation in ananaerobic (no oxygen) environment

Bacterial Reproduction (page 7) Some bacteria can reproduce in just 20minutes! Binary fission Conjugation Endospore

Transformation vs conjugation

Scientists have been able to make possible bacteria and hamster cellconjugation by genetically selecting membrane proteins

Importance of Monerans Some bacteria live in or with other organisms in a relationship where bothbenefit. This is known as symbiosis An example of bacteria and humans would be found in our colon/largeintestine. Bacteria also are important in the recycling of nutrients in theenvironment. They help decompose dead material. Saprophytes are organisms that use the complex molecules of deadorganisms as their energy source of energy and nutrition Note: you are to read p369-372 on your own and summarize/make yourown notes from the textbook readings in a later page with a chartprovided for you to fill out.

Bacteria and Disease (page 9)Food poisoning3 examples:SalmonellaStaphylococciBotulism (from canned food) Clostridiumbotulinum)

Antibiotics are natural substances producedby micro-organisms that attack and destroyother bacteria Example: penicillin

Article: Killing Micro-organisms1. Antibiotic therapy has some problems: Some people are allergic to the antibiotics Antibiotics also kill off the beneficial bacteriaalong with the disease-causing bacteria Can prevent natural immunity fromdeveloping in our bodies and result inreoccurring dependency on antibiotic therapy certain strains of bacteria are showinggrowing resistance to antibiotics

Article: Killing Micro-organisms2. Physicians believe that antibiotics should beadministered only when absolutely necessarybecause: Fear that resistant strains of bacteria willcompletely replace present strains and antibiotictherapy will no longer be effective Adding antibiotics to livestock feed also increasesthe development of resistant strains and thesebacteria can be easily transferred from animals tohumans

Sterilization Kill bacteria by exposing them to heat orchemical action1) Exposing bacteria to high heat. This usuallyinvolves boiling the item or flaming theequipment.2) Chemicals: A disinfectant is a chemical solutionthat kills bacteria .Example: bleach3) Radiation (used in laboratories)

Food spoilage prevention1. Refrigeration2. Cooking food (boiling, frying, steaming)3. Canning food4. Preservatives (sugar, salt , vinegar)

Review Sheet: Bacteria – TypicalMoneransa.b.c.d.e.f.Flagella – long, whip like structures used for movementRibosomes – tiny organelles responsible for making proteinsNucleoid – region where DNA is locatedCell wall – tough outer layer; give bacteria shape & protectionCell membrane – thin layer just inside the cell wall; providesstructural supportCapsule – layer of slime surrounding the cell wall1.2.3.4.binary fissionendosporesLack a nucleusprokaryotic

Self Quiz - ue-green algaeoxygenround, rodlike, spiralflagellumanaerobesbinary fissionsaprophytesmutualism (both speciesbenefit from therelationship)11. moisture, propertemperature12. freezing, refrigeration,canning & radiation13. archaebacteria14. nitrogen-fixing15. mutation16. cyanobacteria17. Actinomycetes (not ontest)18. Spirochetes (not on test)19. Chemosynthetic (same aschemotrophic autotrophs)20. Bacteria (not on test)

Kingdom Monera contained the phylums Archaebacteria and Eubacteria. However due to new discoveries in biochemistry, DNA, etc. these phylums have been rearranged and a new level has been created above the Kingdom taxa called Domain. Kingdom Monera d