Bios 242 Lab Practicum Review Live Lecture Slides PDF

Student Privacy Today’s lecture session is being recorded via audio and/or video means. The recording will be made available to registered students of the sections that were assigned to this lecture. This is intended to supplement the classroom experience. Students are not to record...

Student Privacy Today’s lecture session is being recorded via audio and/or video means. The recording will be made available to registered students of the sections that were assigned to this lecture. This is intended to supplement the classroom experience. Students are not to record today’s webinar via audio and/or visual means, unless they have an approved accommodation from the Office of Student Disability Services. Students are not to reproduce the recordings, share them with others outside their section, or upload them to other online platforms. © McGraw Hill, LLC  Aseptic Technique Which of the following would be examples of good aseptic technique? A. Sterilizing the inoculating loop before using it but not afterwards B. Decontaminating the lab bench both before and after use C. Sterilizing the inoculating loop both before and after using it D. Flaming your loop for at least 10 seconds but then sitting it on the bench before doing your bacterial transfer E. Waving your inoculating loop around in the air to cool it faster F. Flaming the top of your tube to generate upwards air currents before and after inoculating your culture G. Flaming your inoculating loop, dropping it on the floor, but picking it up immediately to use again. © McGraw Hill, LLC  Aseptic Technique Which of the following would be examples of good aseptic technique? A. Sterilizing the inoculating loop before using it but not afterwards B. Decontaminating the lab bench both before and after use C. Sterilizing the inoculating loop both before and after using it D. Flaming your loop for at least 10 seconds but then sitting it on the bench before doing your bacterial transfer E. Waving your inoculating loop around in the air to cool it faster F. Flaming the top of your tube to generate upwards air currents before and after inoculating your culture G. Flaming your inoculating loop, dropping it on the floor, but picking it up immediately to use again. © McGraw Hill, LLC  Scientists Inoculate Various Types of Media to Grow Microorganisms All photos: Kathy Park Talaro © McGraw Hill, LLC  After Incubation, Bacteria Grow in Colonies on Solid Surfaces (a) Lisa Burgess/McGraw Hill; (b) Richard Hutchings/McGraw Hill; (c) Lisa Burgess/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 5  A Bacterial Colony A. Is Macroscopic B. Is Microscopic C. Contains fewer than 100 cells D. Likely contains more than one million cells E. Comes from a single bacterial cell F. Comes from many different bacterial cells all growing together G. Can be seen with the naked eye H. Can be seen in a broth culture I. Is indicated by the red arrow J. Is indicated by the blue arrow © McGraw Hill, LLC 6  A Bacterial Colony A. Is Macroscopic B. Is Microscopic C. Contains fewer than 100 cells D. Likely contains more than one million cells E. Comes from a single bacterial cell F. Comes from many different bacterial cells all growing together G. Can be seen with the naked eye H. Can be seen in a broth culture I. Is indicated by the red arrow J. Is indicated by the blue arrow © McGraw Hill, LLC 7  Cell Shape (Microscopic) and Colony Shape (Macroscopic) Are Not the Same © McGraw Hill, LLC 8  The Streak Plate Method is Commonly Used to Obtain Isolated Colonies WHY???? © McGraw Hill, LLC 9  Microbes Must Have All of Their Required Nutrients In Order to Grow General-purpose media: Grow as many different types of microbes as possible Complex media that contains a mixture of ingredients that support a wide variety of microbial life Limiting Resources: Resource that is not in endless supply and can alter (or limit) the growth of microorganisms Essential elements, food, oxygen, water © McGraw Hill, LLC 10  Microbes Must Have All of Their Required Nutrients In Order to Grow Enriched media: Contains complex organic substances (blood, serum, hemoglobin, or special growth factors) that fastidious bacteria require for growth Blood agar is an example of an enriched media a hemolysis (alpha) – partial lysis b hemolysis (beta) – complete lysis g hemolysis (gamma) – no lysis © McGraw Hill, LLC 11  Some Media Are Used to Grow Specific Types of Microorganisms Access the text alternative for slide images. © McGraw Hill, LLC 12  Some Media Are Used to Differentiate Different Types of Microorganisms Access the text alternative for slide images. © McGraw Hill, LLC 13  Some Media, like MacConkey Agar, are Both Selective and Differential Selective against gram-positive bacteria Differential based on lactose fermentation. + Lactose fermentation = pink - Lactose fermentation = off- white. Describe the colony indicated by the red arrow Describe the colony indicated by the blue arrow © McGraw Hill, LLC 14  Some Media, like MacConkey Agar, are Both Selective and Differential Selective against gram-positive bacteria Differential based on lactose fermentation. + Lactose fermentation = pink - Lactose fermentation = off- white. Describe the colony indicated by the red arrow: Gram- negative; no lactose fermentation Describe the colony indicated by the blue arrow: Gram-negative lactose fermenter © McGraw Hill, LLC 15  Staining is Used to Help Visualize Cells Simple Stains Differential Stains Differential stains show differences between different types of bacteria. Can be used to see more than one species of Simple stains show cell size, bacteria shape, and arrangement © McGraw Hill, LLC 16  Gram-Positive Cells Stain Purple While Gram-Negative Cells Stain Pink © McGraw Hill, LLC 17  The Gram Stain Is a Differential Stain That Can Distinguish Gram-Positive and Gram- Negative Cell Wall Structures © McGraw Hill, LLC 18  In a Controlled Setting, Bacteria Grow in a Predictable Pattern Known as a Growth Curve © McGraw Hill, LLC 19  The Lag Phase of the Growth Curve is a Period of Adjustment and Synthesis. Cells are Not Multiplying at Their Maximum Rate © McGraw Hill, LLC 20  The Log or Exponential Phase of the Growth Curve Will Continue as Long as Environmental Conditions and Nutrition are Favorable. Maximum generation (doubling) time © McGraw Hill, LLC 21  During the Stationary Phase of the Growth Curve, Cells Enter Survival Mode and Grow Slowly. © McGraw Hill, LLC 22  During the Death Phase of the Growth Curve, Cells Die at an Exponential Rate. © McGraw Hill, LLC 23  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Biosafety Level Facilities and Practices Risk of Infection and Class of Pathogens 1 Standard, open bench, no special facilities Low infection hazard; microbes not generally needed; typical of most microbiology teaching considered pathogens and will not colonize the bodies labs; access may be restricted. of healthy persons; Micrococcus luteus, Bacillus megaterium, Lactobacillus, Saccharomyces. 2 At least Level 1 facilities and practices; plus Agents with moderate potential to infect; Class 2 personnel must be trained in handling pathogens can cause disease in healthy people but can pathogens; lab coats and gloves required; be contained with proper facilities; most pathogens safety cabinets may be needed; biohazard belong to Class 2; includes Staphylococcus aureus, signs posted; access restricted. Escherichia coli, Salmonella spp., Corynebacterium diphtheriae; pathogenic helminths; hepatitis A, B, and rabies viruses; Cryptococcus and Blastomyces. 3 Minimum of Level 2 facilities and practices; plus Agents can cause severe or lethal disease especially all manipulation performed in safety cabinets; when inhaled; Class 3 microbes include Mycobacterium lab designed with special containment features; tuberculosis, Francisella tularensis, Yersinia pestis, only personnel with special clothing can enter; Brucella spp., Coxiella burnetii, Coccidioides immitis, no unsterilized materials can leave the lab; and yellow fever, WEE, and HIV. personnel warned, monitored, and vaccinated against infection dangers. 4 Minimum of Level 3 facilities and practices; plus Agents are highly virulent microbes that pose extreme facilities must be isolated with very controlled risk for morbidity and mortality when inhaled in droplet access; clothing changes and showers required or aerosol form; most are exotic flaviviruses; for all people entering and leaving; materials arenaviruses, including Lassa fever virus; or filoviruses, must be autoclaved or fumigated prior to including Ebola and Marburg viruses. entering and leaving lab. © McGraw Hill, LLC 24  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Who Goes Where??? Bacillus anthracis Escherichia coli Ebola Smallpox Lactobacillus from your yogurt © McGraw Hill, LLC 25  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Who Goes Where??? Bacillus anthracis Escherichia coli Ebola Smallpox Lactobacillus from your yogurt © McGraw Hill, LLC 26  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Where does it happen? PPE, goggles, labcoats No special precautions Safety cabinets Oversleeves when working in hood Negative air pressure (air drawn into lab) Clothing changes and showers © McGraw Hill, LLC 27  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Where does it happen? PPE, goggles, labcoats No special precautions Safety cabinets Oversleeves when working in hood Negative air pressure (air drawn into lab) Clothing changes and showers © McGraw Hill, LLC 28  Biosafety Levels are a System of Categories Adopted by the CDC Based on the Relative Danger of the Pathogen Where is this? © McGraw Hill, LLC 29  Phagocytic Cells Clear Debris and Engulf Pathogens Phagocytic Found in blood First to respond Increase during bacterial infections Phagocytic but inefficient and only some things, some times © McGraw Hill, LLC 30  Antibody Molecules BIND (They Do Not Kill) Access the text alternative for slide images. © McGraw Hill, LLC 31  When Activated, Cytotoxic T Cells Kill Infected Self-Cells Access the text alternative for slide images. © McGraw Hill, LLC 32  Sterilization Kills All Organisms. Pasteurization Reduces Spoilage Organisms. Food Spoils Due to Acid Production by Spoilage Organisms. Pasteurization Acronym Temperature Time Reduce or Destroy? LTLT Low 62.8oC 30 minutes Reduce Temperature Long Time HTST High 72oC 15 seconds Reduce Temperature Short Time UHT Ultra High 135oC 1-2 seconds Destroy Temperature © McGraw Hill, LLC 33  Biochemical Tests Help Identify Microbes No color change = No Indole Bubbles = = No Tryptophanase Catalase No color change = No oxidase No bubbles = = No cytochrome c No catalase © McGraw Hill, LLC 34  Describe This Organism Gram Stain = pink rods No movement on motility test No bubbles present in catalase test Color change on indole test No color change on oxidase test Growth only at the top of a fluid thioglycollate tube Pink center when grown on MacConkey agar © McGraw Hill, LLC 35  Describe This Organism Gram Stain = pink rods Gram Negative rod-shaped bacteria No movement on motility test No flagella No bubbles present in catalase test Catalase Negative Color change on indole test Indole Positive; Tryptophanase Positive No color change on oxidase test Cytochrome c Negative Growth only at the top of a fluid thioglycollate tube Obligate Aerobe Pink center when grown on MacConkey agar Lactose Fermenter © McGraw Hill, LLC 36