BIO 152 1st EditionExam # 1 Study GuideLecture 1:I. Introduction What is microbiology? a. Study of microscopic organisms (single celled) II. Cellular MicroorganismsProkaryotes do not have a nucleusa. includes Bacteria i. causes diseases for ex Tuberculosis and food poisoningb. includes Archaeai. are organisms that can live in extreme environments (either very hot or very salty or no oxygen)b. Much simpler, diverse and everywhereEukaryotes have a membrane-enclosed nucleusa. includes Protists (including algae) and FungiIII. Acellular MicrobesVirusesThe cytoplasmic membrane of a prokaryotic cell is not membrane bound, ribosomes are loose in the cytoplasm, and swim in their environment. Viruses are very small, magnify image is 1000x.Anton van Leeuwenhoeck was the first to view microoganisms.IV. Cell FunctionGenetic information processing:These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.DNA replicationTranscriptionTranslationEnergy generation and biosynthesis:GlycolysisRespirationAmino Acid SynthesisLipid synthesisV. Genetic information processing is similar in all organisms. Microorganisms are found almost everywhere on earth.Bacterium: are found in the guts (makes enzymes that digest cellulose), termite gut, on the surface: rod-shaped prokaryotes.Bioiluminescent bacteria in fish: has a light organ, filled with one type of bacterium; produces light and projects light. When the light comes from above and casts a shadow, both will benefit.VI. Hydrothermal vents in ocean floorThis is fluids below earths crusts; microorganisms living here as wellVII. Symbiotic tube worms living near bents are powered by bacteria in their tissues (no mouth or anus)Internal tissue of tube worms.Bacterium eats inorganic H2S (Hydrogen sulfide) and CO2 and provides sugars to the tubeworms and organic nutrients for the worms.Find them in your mouth: example is dental plaque where it is a biofilm (layers of microorganism) comprised of more than 500 species; the sugars from food and these species attach to sugars. The biofilm protects organisms from antibiotics, protects anything and we want to kill them becausethey will destroy gum and cause teeth loss since it may become resistant. In this case, the biofilm is the microorganism.Prokaryotic microorganisms are metabolically diverse. Example: bacteria and archaea (but no plants, animals, or other eukaryotes). These convert N2 to NH4 (called nitrogen fixation)Some microogranisms (pathogens) cause disease. Majority are not pathogenic.VIII. Classification of Organisms & Phylogenetic TreeSequence analyses of ribosomal RNA reveals the 3 domains of life. rRNAs ae ideal molecules to construct a phylogenetic tree because:All organisms have ribosomes and rRNA does not change rapidly.3 Domains: Bacteria, Archaea, and Eukarya (all eukaryotic organisms) Microorganisms dominate the phylogenetic tree. VIIII. History of Life on EarthProkaryotes formed 3 Billion Years Ago. Microbes were anaerobic meaning no oxygen was present. Anaerobic environment means no oxygen was present. It became present when cyanobacteria came to exist (it is blue green algae, carry outs photosynthesis just like oxygenic photosynthesis and releases oxygen).Mitochondria is the site of respiration. Chloroplasts is the site of photosynthesis. Eukaryotic cells get mitochondria from bacteria.Endosymbiotic theory: engulfs bacteria and was an advantage. When cyanobacteria was engulfed by eukaryotic cells it gave rise to plants and algae. X. Names of MicroorganismsGenus speciesi.e. Genus is capitalized and the species is italicized. Example: Bacillus subtilis or B. subtilis (common bacterium)XI. Why study microbes?Allows humans to prevent food spoilage and prevent disease occurrence.Allowed development of aseptic techniques (sterility) to prevent contamination in medicineLearn about cell processesManipulate microorganisms for biotechnologyXII. Important areas of microbiologyMedical microbiologyEnvironmental microbiologyFood microbiologyBiotechnology - use of microbes to make specific productsMicrobes as model organisms Microbial ecology:Bacteria recycles carbon, nutrients, sulfur, and phosphorus that can be used by plants and bacteria. Bioremediation: Bacteria degrade organic matter in sewage.Bacteria degrade or detoxify pollutants such as oil and mercury. Biological insecticides:Bacillus thuringiensis infections are fatal in many insects but harmless to other animals and plants. Biotechnology: the use of microbes to produce foods and chemicals.Lecture 2: Cell Structure and FunctionThe prokaryotes are small and are typically small (usually .5 to 2 micrometers in diameters). Eukaryotic cells are larger usually 10 to 50 micrometers in diameters. Smaller size of prokaryotes is an advantage when it comes to nutrient utilization which results in faster growth and larger populations. Prokaryotes lack a membrane enclosed nucleus. Bacteria and Archaea are both small; Bacteria is abundant and is mostnot harmful; Archaea is the less common; often found in extreme environments; none are pathogenic meaning they cannot cause disease. Reproduction is by binary fission (divides by splitting into two; exponential); to count bacterial cells we place on agar surface and count calories that grow; use fluorescent dye that binds bacterial DNA to directly count bacteria. Cell shape: major shapes are spheres, rods, cocci, bacilli, vibrios, and spirochetes. Some occur as single cells, pairs, and filaments. Bacterial cell: cytoplasm, outer membrane/cell wall, and appendages.Cytoplamic membrane: similar to cytoplasmic membrane of eukaryotic cells, has a lipid bilayer (made upof phospholipids and proteins), has fluid mosaic structure (fluid, not rigid; has proteins and lipids), and has 2 layers of phospholipids and proteins which are embedded in membrane (integral membrane proteins).Glycerol and fatty acid makes the phospholipid. Important to know that it has 1 polar tail (likes water; hydrophillic) and 1 nonpolar tail (doesn’t like water; hydrophobic). Functions of Bacterial Cytoplasmic Membrane:1. Barrier2. Transport Proteins (nutrients to cell, and export things that are bad)3. Has many metabolic enzymes (where respiration takes place)Proteins are needed for respiration (Proton Motor Force and energy)Important to note that unlike eukaryotes, components of electron transport chain are in bacterial cytoplasmic membrane.