Microbiology Midterm Study Guide for Dr. Bradbury's Course, Study Guides, Projects, Research of Nursing

Download Microbiology Midterm Study Guide for Dr. Bradbury's Course and more Study Guides, Projects, Research Nursing in PDF only on Docsity! Microbiology Midterm Study Guide: Midterm: March 20, 2020 Dr. Bradbury Course outcome 1: (Discussed on pp. 29-33) I. Covalent Bonds: A chemical bond formed when two or more atoms share electrons. II. Ionic Bond: A chemical bond that’s formed when an atom transfers an electron to another atom. III. Hydrogen bond: A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other. IV. What types of bonds are found in carbohydrates? Covalent bonds which are found in the glyosidic linkages. V. What types of bonds are found in nucleic acids? Hydrogen bonds which are found between the bases. VI. What type of bonds are in proteins? Covalent bonds which are found in those peptide bonds. VII. What types of bonds are in lipids? Covalent bonds which are found between the glycerol and the three fatty acids of a triglyceride. VIII. Properties of viruses?  Capsid: protein shell of a virus.  Multiple different strands of genetic material  Require a host and carry proteins which “hook” on to their host to infect. IX. Scientist contribution to microbiology?  Fredrick Griffith: He discovered transformation. His experiment tested mice & pneumonia. He gave mice either rough or smooth strands of the virus and sometimes heat fixed the sample of the virus. He found that when he put live rough viruses and heat killed smooth, the rough transferred its genetic material to the smooth one.  Louis Pasteur: He discovered pasteurization & disapproved spontaneous generation. He added nutrient broth to two flasks and bent the neck of one into swan ‘s’ shapes. He then boiled them to kill off the microbes. The swan neck shaped flask was fine, whereas the flask without the curve in the neck was cloudy. This disapproved  Transformation: The acceptance by a bacterial cell of small fragments of soluble DNA from the surrounding environment.  Conjugation: A mode of genetic exchange in which a plasmid is transferred from a donor to a recipient cell via a direct connection.  Transduction: The process by which a bacteriophage serves as a carrier of DNA from a donor cell to a recipient cell.  Transposable elements: Segments of DNA that insert themselves into new locations within a genome. III. Types of mutations:  Lethal mutation: Mutations that lead to cell dysfunctions or death.  Neutral mutations: mutations that do not cause adverse or helpful changes.  Point mutations: Affects only a single nucleotide (base) in a gene. Involves insertion, deletion, or substitution of single bases. IV. What are types of RNA in a cell?  mRNA (messenger): Carry information from DNA to the site of protein synthesis.  tRNA (transfer): Carries amino acids to the ribosome; during translation tRNA pairs it’s anticodon with a codon on the mRNA; amino acid is inserted into the growing peptide chain (chain makes a protein).  rRNA (ribosomal): Makes polypeptides (assemblies of amino acids) that go to make up protein factory. V. What are triglycerides made up of? A glycerol & 3 fatty acids. VI. Describe the cell envelope in a gram-positive cell of bacteria? Two layers; a thick cell wall composed of primarily of peptidoglycan & the cytoplasmic membrane. Describe the cell envelope of a gram-negative cell of bacteria? Three layers; An outer membrane (contains a lipopolysaccharide), a thin cell wall & a cytoplasmic membrane. VII. Steps of mitosis:  Interphase: Replication of DNA  Prophase: Nuclear membrane breaks down.  Metaphase: Chromosomes line up in the middle of the cell.  Anaphase: Sister chromatids are separated  Telophase: Nuclear membrane reforms. Course outcome 3 I. Lenses in the microscope.  Ocular lens: The eyepiece that provides a re-magnified image for you to see when light enters through the objective lens.  Objective lens: The lens closest to the specimen which forms the real image. II. Different medias  Complex media: Contains at least one ingredient that is unknown (like blood).  Defined media: The exact chemical composition is known.  Selective media: Contains an agent that inhibits the growth of a particular microorganism.  Differential media: Allows growth and visibility of many types of microorganism. III. The five I’s of studying microorganisms:  Inoculation: Introducing microorganisms into a culture where they can grow and reproduce.  Incubation: Placing an inoculated culture into a temperature-controlled chamber for growth (called an incubator).  Isolation: The separation of a strain from a natural, mixed population of living microbes, as present in the environment.  Inspection: Appearance, cells, colony (red, shape, gram stain, sugar, etc).  Identification: Determine type of microbes, specialized tests; biochemical test to determine metabolic activities specific to microbes, immunologic tests, genetic analysis. Course outcome 4 I. Competitive Inhibition: A molecule that resembles the substrate occupies the active site, preventing the substrate from binding. II. Noncompetitive Inhibition: Inhibitor attaches to enzyme away from active site to change the shape of it. The substrate can no longer bind to the enzyme. III. The ability of fungi to grow in high concentration of sugar or salt: Osmotic pressure (End of chapter 11). VI. Protozoan form (pg. 126): Unicellular, with pseudopods, cilia and flagella. Most are harmless. VII. Protozoan function: Mainly harmless but can sometimes be a parasite. Course outcome 7 I. Prion: An infectious protein particle. II. Viroid: Infectious pieces of naked RNA. Only infects plants. Course outcome 8 I. Methods of achieving sterilization: Heating the tools before and after use, proper usage of gloves and jackets etc. II. Disinfection: The destruction or removal of vegetative pathogens but not bacterial endospores. III. Sterilization: The complete removal or destructive of all viable microorganisms including endospores. IV. Antisepsis/degermation: Chemicals (antiseptics) applied to body surfaces to destroy or inhibit vegetative pathogens. V. Decontamination/sanitization: The mechanical removal of most microbes. VI. Broad spectrum antibiotic: Able to work on a gram negative and gram-positive bacterium (Think of ampicilin). VII. Narrow spectrum antibiotic: Effective on only a select group of microorganisms (think penicillin). VIII. Mechanisms of antibiotic resistance: 1. Enzymatic destructive of drug, 2. Prevention of prevention of drug, 3. Alteration of drug’s target site, 4. Rapid ejection of the drug. IX. Sulfonamide mechanism of action: They interfere with other metabolic processes. They act against the folic acid synthesis which prevents further metabolism. X. Silver nitrate uses in disease treatment: It was used to treat gonococcal infections in the eyes of newborns exposed in an infected birth canal. Course outcome 10 I. Patterns of infection  Local Infection: The infection is only in a particular region of the body (Boils, fungal skin infections, Warts).  Systemic Infection: An infection throughout the whole body (chicken pox, typhoid fever & histoplasmosis).  Focal Infection: A systemic infection that starts locally (TB, scarlet fever, toxemia).  Mixed Infection: An infection where lots of different microbes grow at the same time.  Primary infection: An initial infection.  Secondary Infection: Another infection that is caused by a different microbe.  Acute Infection: Rapid, but short lived (common cold).  Chronic Infection: An infection that lasts a long time (herpes) II. Carrier types  Asymptomatic: No symptoms.  Incubation type: Those who can transmit the illness before they even know that they have it.  Convalescent period: Someone who may feel better, but it can still be transferred.  Chronic passive carrier: Someone who has the infection long term with minimal affects but it can still be transferred. III. Stages in the course of infection and disease (I Pet Pretty Cats).  Incubation period: The time from initial contact with the infectious agent to the appearance of first symptoms.  Prodromal period: When the earliest notable symptoms of infection appear.  Period of invasion: Infectious agent multiplies at high levels, exhibits its greatest virulence, and becomes well established in its target tissue.  Convalescent stage: Patient responds to infection and symptoms decline. IV. Opportunistic Infections: Infections that strike people whose immune system are weakened. V. Phagocytosis: When the cell uses its membrane to engulf something. VI. Sequelae: Long term damage to tissue or organs. VII. Sign versus symptoms:  Signs: Any objective evidence of disease as noted by an observer (fever).  Symptom: Subjective evidence of disease as sensed by the patient (Nausea). VIII. Emerging disease: caused by newly identified microbes (COVID-19). IX. Reemerging disease: Diseases that affected humans in the past, but that are becoming more prevalent (Diseases caused by antibiotic resistant bacteria).