...Biology 100 GROWTH OF BACTERIA INTRODUCTION We share our environment with various and diverse microorganisms. Humans harbor various bacteria on their skin, in their upper respiratory tract, and in their alimentary canals. There are very few, if any, environments in nature in which bacteria do not exist. Bacteria have been isolated from such diverse environments as sulfur hot-springs associated with volcanic activity to super-cooled waters of the Antarctic. This lab will consist of two parts. Each part will involve discussion and set-up during the first week and the reading of the results on the second week of the lab. Part 1 Bacteria in our environment You will identify some parts of your local environment you wish to test for the presence of bacteria. Part 2 Effectiveness of hand washing You will be conducting an experiment to test the effectiveness of various hand-washing methods and their effects on bacteria. MATERIALS & METHODS Part 1: Bacteria in our environment. Work in groups of two. Week 1 1. Decide what parts of your local environment you wish to sample for bacteria. 2. Obtain a sterile TSA (Trypticase soy agar) plate. Keep it sterile, do not open yet! 3. Label the bottom of the plate with the following: - students initials or names - type of exposure - date of exposure 4. Expose the...
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...MBK – Lab Report Name: __Jade Smart___ Section: ___________________ Aseptic Technique and Culturing Microbes Part 3: Generating Microbial Cultures: Observe your organisms after 24 hours to assess the growth patterns of all tubes. If there is no observable growth allow the tubes to incubate an additional 24 hours. Record your observations. Questions: A. What is the difference between a bactericidal and bacteriostatic agent? Between sterilization and disinfecting? The difference between the two is that bactericidal kills bacteria directly. While bacteriostatic stops the bacteria from growing. Bactericidal will injure the plasma membrane and the cell will leak out, killing it. Bacteriostatic stops bacteria from replicating. The main difference between sterilization and disinfection is, that sterilization kills all microorganisms, while disinfection eliminates harmful microorganisms from inanimate objects and surfaces. Sources: http://study.com/academy/lesson/types-of-antibiotics-bacteriocidal-vsbacteriostatic-narrow-spectrum-vs-broad-spectrum.html http://www.diffen.com/difference/Disinfect_vs_Sterilize B. List five sterilization methods, how they work, and what they are used for. The first form is steam. A machine called an autoclave is heated to 121-134 degrees Celsius. You hold the object there for 15 minutes for 121 degree Celsius or 3 minutes at 134 degree Celsius. It is used to inactivate all fungi, bacteria, viruses,...
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...MicroBiology- MLT1 LabPaq / Published by: Hands-On Labs, Inc. sales@labpaq.com / www.LabPaq.com / Toll Free 866.206.0773 A Laboratory Manual of Small-Scale Experiments for the Independent Study of Microbiology 50-0222-MB-01 LabPaq® is a registered trademark of Hands-On Labs, Inc. (HOL). The LabPaq referenced in this manual is produced by Hands-On Labs, Inc. which holds and reserves all copyrights on the intellectual properties associated with the LabPaq’s unique design, assembly, and learning experiences. The laboratory manual included with a LabPaq is intended for the sole use by that LabPaq’s original purchaser and may not be reused without a LabPaq or by others without the specific written consent of HOL. No portion of any LabPaq manual’s materials may be reproduced, transmitted or distributed to others in any manner, nor may be downloaded to any public or privately shared systems or servers without the express written consent of HOL. No changes may be made in any LabPaq materials without the express written consent of HOL. HOL has invested years of research and development into these materials, reserves all rights related to them, and retains the right to impose substantial penalties for any misuse. Published by: Hands-On Labs, Inc. 3880 S. Windermere St. Englewood, CO 80110 Phone: Denver Area: 303-679-6252 Toll-free, Long-distance: 866-206-0773 www.LabPaq.com E-mail: info@LabPaq.com Printed...
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...LAB6_AEROBIC AND ANAEROBIC GROWTH As humans, we are accustomed to thinking that oxygen is essential to life. Microorganisms, however, are quite adaptable and diverse and vary considerably in their oxygen requirements. Some bacteria require oxygen; some can grow with or without it and some are actually killed by oxygen. Bacteria are generally classified into three main groups with respect to oxygen: 1. Obligate aerobes: Like humans, these organisms have an absolute requirement for oxygen. Because aerobic metabolism generates the toxic byproduct hydrogen peroxide, obligate aerobes must produce the enzyme catalase which breaks down hydrogen peroxide to water and oxygen gas. 2. Obligate anaerobes: Not only do these organisms not require oxygen, they are often killed in its presence. Because anaerobic metabolism does not generate hydrogen peroxide, obligate anaerobes generally do not produce catalase. The causative agent of botulism, Clostridium botulinum is an obligate anaerobe. Since the canning process removes the air, Clostridium botulinum can grow in inadequately sterilized canned foods. This isn't normally a problem in fresh foods since they are exposed to air. 3. Facultative anaerobes: These organisms will use oxygen in their metabolism if it is available, but can also grow without oxygen. Again, since aerobic metabolism generates hydrogen peroxide, they produce catalase. E. coli, which is normal flora of the intestine, is an example of a facultative...
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...The Diversityof Life Lab Manual Stephen W. Ziser Department of Biology Pinnacle Campus for BIOL 1409 General Biology: The Diversity of Life Lab Activities, Homework & Lab Assignments 2013.8 Biol 1409: Diversity of Life – Lab Manual, Ziser, 2013.8 1 Biol 1409: Diversity of Life Ziser - Lab Manual Table of Contents 1. Overview of Semester Lab Activities Laboratory Activities . . . . . . . . . 2. Introduction to the Lab & Safety Information . . . . . 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 15 30 39 46 54 68 81 104 147 3. Laboratory Exercises Microscopy . . . . . . Taxonomy and Classification . Cells – The Basic Units of Life . Asexual & Sexual Reproduction Development & Life Cycles . . Ecosystems of Texas . . . . The Bacterial Kingdoms . . . The Protists . . . . . . The Fungi . . . . . . . The Plant Kingdom . . . . The Animal Kingdom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 13 17 22 26 29 . 32 . 42 . 50 . 59 . 89 4. Lab Reports (to be turned in - deadline dates as announced) Taxonomy...
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...------------------------------------------------- Microbiology Lab Report 3 Carolina Toscanojara Antibiotic Sensitivity. Objective: Antibiotics are chemical compounds that selectively interfere with the growth of microorganisms while causing little or no damage to the animal or human host. The purpose of this lab was to determine the effectiveness antibiotics against any given bacterium by means of examining the zone of inhibition, the minimum inhibitory concentration, and the minimum bactericidal concentration. Introduction: Chemical antimicrobial agents are chemical compounds that are capable of either preventing the microorganisms for multiplying (bacteriostatic) in order for the immune system of the host to overcome them or killing them completely (bactericidal). Antibiotics taken to improve the symptoms from a disease are called chemotherapeutic drugs; they are produced by a microorganism such as bacterium or fungus and/or are derived from a chemical produced by one. The test carried out to determine which antibiotic will be most successful in treating certain bacteria is called Antibiotic Susceptibility Test (AST) and it is often done by the Kirby-Bauer method, which uses Muller Hinton agar and paper discs containing specific concentrations of antibiotics are placed on the agar surface after rubbed with bacterial specimen. Results of AST are examined for zones of inhibition around each disk after incubation; this is called minimum inhibitory concentration (MIC). The diameter of the zone of growth inhibition is measured...
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...Introduction: The microbiology of food and the environment are two very important fields in the large scope of microbiological research. Because microorganisms exist almost everywhere, it is important to determine the influences that they place on the food we depend on for survival, and the environment in which we humans call home. In this lab, we conducted five experiments in these two fields, and in doing so gained a better understanding of the influences and importance of microbes in food and the environment. The first exercise was the enumeration of soil microbes. This experiment showcased the immense diversity of bacteria, actinomycetes, and fungi found in soil. This diversity ranges from microbes that are beneficial to the environment by decomposing dead organic matter into energy sources usable by other organisms, to the pathogenic bacterial and fungal spores that can infect humans and animals alike. The techniques used are serial dilutions, which allow for quantification and a close estimation of the amount of said organisms found in a soil sample. (1) The second exercise that we conducted was the microbiology of water experiment. This is a very important standardized experiment used to determine the density of coliforms found in a 100 mL sample of water. It also can be used more specifically to determine the density of Escherichia coli, which can cause food poisoning amongst other illnesses. The techniques used are the multiple tube fermentation method, which involves...
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...In order to receive full credit each of your lab reports MUST include a purpose, summary, detailed answers to the lab questions which demonstrate your understanding of the concepts as well as a conclusion that summarize the lab and specifically addresses the lab’s learning objectives and relate them back to the data or observations collected in the lab. Purpose: Briefly state the learning objective of the assigned lab in two sentences. This assignment is for us to understand how to convert basic measurements. It is important to know how other parts of the world calculate temperature and other measurements so that we are on the same page and are able to communicate with each other. Summary: Detail and explain what was observed during the lab activity; this answer should be approximately one paragraph in length....
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...Microbiology 197 (S12) Laboratory Report Format: Name: Lindsey Orlando Date: 4/28/2012 Laboratory: Enterobacteriaceae ID – Tube Method A. Organism(s): (Each organism must be written-up separately). 1. Which new organism(s) was introduced by the instructor? Give both the genus and species. Serratia marcescens 2. For each organism introduced by the instructor provide the following information. a. Macroscopic colony characteristics: (On a typical growth media) Medium Gray α b. Microscopic characteristics: (As seen on a stained slide preparation) Gram negative rod singles c. Which disease(s) is caused by the organism? Nosocomial catheter associated infections, urinary tract infections, and wound infections. d. Signs and symptoms for one disease given in (c). A strong, persistent urge to urinate, burning sensation when urinating, passing frequent, small amounts of urine, urine that appears cloudy, urine that appears bright pink or brown in color (signs of blood in the urine), strong-smelling urine e. Significant additional information. I.e. drug resistance, special growth requirements, vaccines available, etc. (As given by the instructor or found in your reading.) Serratia marcescens is also a common bacteria found in the shower. It is easily identified by the pink color slime. This microorganism shows to have resistance to many antibiotics including: penicillin as...
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...Lab Report 3: Effect of UV Light on Microbial Growth Kristin Holmes – April 2, 2013 PURPOSE: The purpose of this lab is to determine the effects of ultraviolet light on microbial growth and the effectiveness of the repair mechanisms of light repair and dark repair on UV damage. INTRODUCTION: Can Ultraviolet (UV) light be a viable form of sterilization and/or disinfection? This lab experiment will look to examine and answer that question. UV light is a form of electromagnetic radiation that is invisible to the human eye. It has a short wavelength and is considered high energy which allows it to pass through some materials. The biological effects are potentially devastating based on the length of exposure and the length of the wavelength exposed to. The reason UV light can be so detrimental is due to its effect on DNA and the mutations that can occur because of exposure. The absorbance of UV photons causes the formation of pyrimidine dimers; these in turn create challenges to DNA replication. While DNA repair mechanisms can remove these dimers, with increased exposure and/or repeated exposure as well as incomplete repair, DNA replication is not always exact. (Aishwariya) UV radiation is typically placed into one of three categories. UV-A radiation is the longest wavelength and has the least damaging effect. UV-B radiation is medium length and UV-C is the shortest wavelength. (Aishwariya) UV-A radiation can have long term effects; however the most damage, on the cellular level...
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...Comparing Growth of E. Coli at 37°C and 25°C and on rich and minimal mediums Lab report 1 Richard Montez MCB 3020L Monday 2 pm June 15, 2013 Abstract: Bacteria is a very diverse creature, and can grow in extreme conditions. There are two variables that factor in finding out what are more optimal conditions in which E. coli can grow, temperature and difference in medium. The two ways to determine the amount of bacteria growth are: optical density by using the spectrophotometer, and also the 10-fold serial dilution, the latter of which is the most accurate way. The 4 phases: lag phase, log phase, stationary phase and death phase, show the strength of the life cycle of a bacteria cell. The results show that at 37°C (normal body temperature) and the LB agar plate (rich medium) gives E. coli better optimal conditions to grow. Introduction Although bacteria is composed of only a single cell, they are extremely involved and we have so much to learn about these creatures. Bacteria can live in some of the most extreme temperatures- from temperatures that could potentially freeze the blood under your skin, to the other end of the spectrum where they could be found at temperatures near 100°C at the mid-ocean volcanic vents. The bacteria we chose to further learn about it's optimal growth conditions was Escherichia Coli. There are two variables in this experiment, temperature and choice of medium. The first variable, the sample was incubated E. Coli at 25°C...
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...Clinical Microbiology Lab Final December 13, 2013 Table of content Gram Stain Technique……………………………………………………………………………………………… page 1 Culture Transfer Technique……………………………………………………………………………………… page 2 Acid-Fast Stain Technique………………………………………………………………………………………… page 3 The importance of the Gram Stain Technique to a physician……………………………………. page 4 The importance of varying shapes/colonies formation of bacteria……………………………. page 5 Spore Stain Technique………………………………………………………………………………………………. page 6 The Importance of incubation/protocol techniques…………………………………………………... page 7 The importance of various types of media for bacterial growth…………………………………. page 7 The importance of biochemical analysis in the microbial process……………………………… page 8 The importance of studying Clinical Microbiology and how the course will assist me in reaching my professional goals……………………….. page 9 Bibliography……………………………………………………………………………………………………………… page 10 Gram Stain Technique The Gram Stain is one of the most important differential stains used in bacteriology. (Cappuccino and Sherman, Microbiology A Laboratory Manual) Using the gram stain it is possible to determine purple gram-positive cells (S. aureus) from pink gram-negative cells (E. coli). The results of the Gram Stain make it possible to identify microorganisms by their shape, number and morphology. In a clinical setting these results can help in treatment by identifying the type of microorganism...
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...have certain bacteria that are considered good bacteria and therefore treating an infection with a selectively toxic agent would preserve the healthy bacteria in our body. B. Broad spectrum antibiotics are effective in inhibiting growth in a wide variety of both gram-positive and gram-negative bacteria. Such antibiotics are very important when time is limited in determining what kind of bacteria is causing a life-threatening infection. They are also beneficial when the exact bacteria that is causing the infection is unknown. Also, some infections are not just caused by one type of microorganism. However, there are certain types of bacteria that have developed resistance to broad spectrum antibiotics. Narrow-spectrum antibiotics are effective against killing just gram-positive or just gram-negative bacteria. They target the bacteria that is causing the infection while not killing as many or any of the normal bacteria. These antibiotics also cause less resistance to the bacteria. A disadvantage of narrow-spectrum antibiotics is that they can only be used to treat an infection in which the bacteria that has caused it is known. C. Certain enzymes may cause inactivation of antibiotics which causes resistance to antimicrobial agents. The bacteria’s target site may change in some way which reduces the effectiveness of antimicrobials. Certain bacteria are able to neutralize the agent and even prevent the agent from getting into the bacteria. Some bacteria may become...
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...IDENTIFICATION OF UNKNOWN BACTERIA It is virtually impossible to identify bacteria based on physical characteristics alone. This is due to the fact that there are only a few basic shapes and physical features commonly seen in the prokaryotic world. Instead, biochemical testing has been used to make bacterial identification down to the “species” level. These schemes are based on creating and matching biochemical profiles of the production of enzymes, acids and gases by isolated pure cultures of a given microorganism. Identification schemes and flow charts can be found in reference texts such as “Bergey’s Manual of Determinative Bacteriology” or “The Prokaryotes”. Each group of students will receive a TSA slant or broth containing a pure culture of an unknown bacterium belonging to the Family Enterobacteriaceae. It is the responsibility of the group to maintain stock cultures of the organism provided. Working stock cultures will be used to inoculate the various biochemical test media over the next several weeks and should be fresh and free from contaminants. A reserve stock culture should be made and after incubation and comparison with the original slant, kept with the original slant in the refrigerator. It is critically important that aseptic techniques are used during transfers and inoculations to prevent contamination of your cultures. If contamination is suspected, you will be able to fall back to your reserve stock. If you fail to maintain a reserve stock...
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...BACTERIA AND ANTIBIOTICS LAB REPORT Bryan Bennett Ms. Johnson Biology 09 period 8 March 12, 2013 Introduction: 1. Eubacteria -Has cell wall with peptidoglycan -They can live nearly anywhere on earth (sky to underground) -Unicellular -Prokaryotic -Reproduce Asexually Archaebacteria -Cell wall without peptidoglycan -Live in environments without oxygen (anaerobic) -Prokaryotic -Unicellular -Reproduce Asexually -Oldest bacterial form -Unique lipids in their cell membrane -DNA sequence is more like other Eukaryotes than other bacterial types (eubacteria) 2. Bacteria are classified into four groups: * PHOTOAUTOTROPHS * PHOTOHETEROTROPHS * CHEMOAUTOTROPHS * CHEMOHETEROTROPHS 3. 4. Many bacteria are heterotrophic which is to thrive off other organisms. The type of bacteria that causes disease are heterotrophic parasites. There are also many harmless bacterial parasites, many of which can be helpful to their hosts. Autotrophic bacteria manufacture their own food by chemosynthesis and photosynthesis. In aerobic respiration a series of reactions convert glucose to carbon dioxide and water and give off energy. Free oxygen is required as the final acceptor for electrons and hydrogen to form water. Bacteria, able to grow in the presence of oxygen, are called aerobic bacteria. Pseudomonas is an example of aerobic bacteria. In anaerobic respiration free oxygen isn’t required. Organic compounds are the final electron acceptors in anaerobic...
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