Growth of Microorganisms

In: Science

Submitted By hongjacku
Words 288
Pages 2
Growth of Microorganisms
Culturing is the growing of micro-organisms in prepared media in the laboratory. The prepared medium is called the ‘culture medium’. Bacteria, fungi and algae grow easily in test-tubes, flasks or Petri dishes of culture media. Virus on the other hand, can only grow and multiply inside living cells, so they cannot be grown in a culture medium.
Micro-organisms are able to increase in size and multiply in number of cells. The growth of micro-organisms is measured based on increase in population size rather than increase in cell size. Under favourable conditions (food, adequate temperature and humidity) micro-organisms reproduce asexually by binary fission. Generation time varies from species to species e.g. rapidly growing specie like Escherichia coli can divide every 30minutes.

Two methods are used to measure the growth of micro-organisms;
(i) First Method: This involves inoculating a bacterial sample into a nutrient broth. As the bacterial population increases, the clear liquid medium becomes cloudy / turbid. Increase in turbidity indicates an increase in number of bacterial cells. Turbidity can be measured using a spectrophotometer. Thus by measuring the turbidity of a bacterial culture in nutrient broth at regular intervals, the growth of a bacterial population can be measured.
(ii) Second Method: This involves taking small samples of bacteria from a nutrient broth at regular intervals of time and diluting the samples several times. Each diluted sample is then inoculated onto a nutrient agar medium in a petri dish and incubated. The number of colonies formed in each petri dish is counted and this indicates the number of living bacterial cells in the diluted sample. From this, the actual number of bacteria in the original sample can be…...

Similar Documents

Growth

...line that is associates with ... a. Motorola b. Microsoft c. Siemens d. Accenture This country's first lunar probe Chang'e-1 crashed on moon successfully (that was planned) in 2009. This Chang'e-1 belongs to… a. Israel b. Iran c. China d. Saudi Arabia ‘Next’, is the name of the retail chain of …. a. Marico Industries b. Dabur Industries c. Videocon Industries d. None of these General Knowledge Take Off MBA Test Prep Page: 19 42. 43. This person was appointed as the Federal Chief Information Officer in the Obama administration and is the highest ranking Indian American in the administration. Who are we talking about here? a. Aneesh Paul Chopra b. Raj Shah c. Vivek Kundra d. None of these ‘Powering growth responsibly’, is the tag line that you would associate with… a. NHPC b. BHEL c. NTPC d. SAIL 44. Vittorio Colao will be the new chief executive officer of this telecom giant. We are talking about… a. AOL b. Telmex c. Reliance Infocomm d. Voldafone Plc. 46. Can you identify the name of the Indian industrialist who bought Gandhiji's belongings in a deal worth $1.8 millions recently? a. Ratan Tata b. Vijay Mallaya c. Mukesh Ambani d. Sunil Bharti Mittal 48. You would associate Karun Chandhok with … a. Golf b. Car racing c. Table Tennis d. Lawn-Tennis 49. Scooty Streak is an automobile brand that belongs to… a. Hero Honda b. TVS Motors c. Kinetic Engineering Ltd. d. Bajaj Auto......

Words: 14520 - Pages: 59

Microorganism

...Microorganism The study of microorganisms is called microbiology. Microorganisms include bacteria, fungi, archaea or protists, but not viruses and prions, which are generally classified as non-living. Most microorganisms are single-celled, or unicellular, but some are microscopic, and some unicellular protists are visible to the average human. Microorganisms live almost everywhere on Earth where there is liquid water, including hot springs, on the ocean floor, and deep inside rocks within Earth's crust. Microorganisms are critical to nutrient recycling in ecosystems as they act as decomposers. As some microorganisms can also fix nitrogen, they are an important part of the nitrogen cycle. However, pathogenic microbes can invade other organisms and cause diseases that kill millions of people every year. Microorganisms can be found almost anywhere in the taxonomic organization of life on the planet. Bacteria and archaea are almost always microscopic, while a number of eukaryotes are also microscopic, including most protists and a number of fungi. Viruses are generally regarded as not living and therefore are not microbes, although the field of microbiology also encompasses the study of viruses. Habitats and ecology Microorganisms are found in almost every habitat present in nature. Even in hostile environments such as the poles, deserts, geysers, rocks, and the deep sea, some types of microorganisms have adapted to the extreme conditions and sustained colonies; these......

Words: 496 - Pages: 2

Growth

...VERMICOMPOST TEA: EFFECTS ON PAK CHOI (BRASSICA RAPA CV . BONSAI, CHINENSIS GROUP) GROWTH AND YIELD, PHYTONUTRIENT CONTENT AND SOIL BIOLOGICAL PROPERTIES A DISSERTATION SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI’I IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN TROPICAL PLANT AND SOIL SCIENCES AUGUST 2011 By Archana P. Pant Dissertation Committee: Theodore J. K. Radovich, Co-Chair Nguyen V. Hue, Co-Chair Robert E. Paull Susan C. Miyasaka Norman Q. Arancon Brent S. Sipesi ACKNOWLEDGMENTS I wish to thank my Co-Advisors, Dr. Theodore J. K. Radovichand Dr. Nguyen V. Hue, for their guidance, encouragement, and continuous support throughout my graduate program. I am grateful to my dissertation committee members; Dr. Robert E. Paull, Dr. Susan C. Miyasaka,Dr. Norman Q. Arancon and Dr. Brent S. Sipes for their intellectual comments, suggestions and encouragements. This research was supported by grants from the Western Sustainable Agriculture Research and Education (WSARE)and the Tropical and Subtropical Agriculture Research (TSTAR) Programs of the USDA.I appreciate the services provided by Waikiki Worm Company, HI, the Agricultural Diagnostic Service Center, University of Hawaii, Microbial Matrix Systems, OR, and the National Research Council, Saskatoon, Canada. I would like to thank Dr. Teresita Amore, Dr. J. P. Bingham and Dr. Travis Idol for granting me access to their laboratories......

Words: 657 - Pages: 3

Growth

...except that one has a higher saving rate. According to the Solow-Swan growth model, in the steady state the country with the higher saving rate will have ______ level of total output and ______ rate of growth of output per worker as/than the country with the lower saving rate.| A)|the same; the same| B)|the same; a higher| C)|a higher; the same| D)|a higher; a higher| 2.|Examination of recent data for many countries shows that countries with high saving rates generally have high levels of output per person because:| A)|high saving rates mean permanently higher growth rates of output.| B)|high saving rates lead to high levels of capital per worker.| C)|countries with high levels of output per worker can afford to save a lot.| D)|countries with large amounts of natural resources have both high output levels and high saving rates.| 3.|The Golden Rule level of capital per worker is the steady state level of capital per worker with the highest level of:| A)|output per worker.| B)|capital per worker.| C)|savings per worker.| D)|consumption per worker.| 4.|In the Solow-Swan growth model of an economy with population growth but no technological change, if population grows at rate n, then the total stock of capital grows at rate ______ and total output grows at rate ______.| A)|n ; n| B)|n ; 0| C)|0 ; 0| D)|0 ; n| 5.|In the Solow-Swan growth model of an economy with population growth but no technological change, if population grows at rate n, total......

Words: 1385 - Pages: 6

Bacterial Growth Rates

...Unit 3. Assignment 1: Bacterial Growth Rates 1. Mediums that could be used to determine shigellosis include Btilliant Green Agar, and Triple Sugar-Iron Agar. Expected results in a confirmed case of shigellosis are as follows: Brilliant Green Agar – Isolated Shigella colonies which do not ferment lactose or sucrose and appear red or white in color with no growth to trace growth on the Agar plate will be present. Triple Sugar-Iron Agar – Presence of Shigella will manifest as a red slant with a yellow butt with no H2S present. In Brilliant Green Agar, E. coli O157 would present as isolated yellow to greenish colonies surrounded by yellow-green zones. In the Triple Sugar-Iron Agar, E. coli O157 will manifest as a red slant, red butt indicating no change and no sugar fermented. These growth results and their marked differences would allow for distinguishing between E. coli and shigellosis (Black, 2012). 2. To separate a mixed culture of S. aureus, S. epidermidis, and P. aeruginosa into three pure cultures, the following procedure should be used: a) Make an isolation plate by diluting the mixed culture until the individual organisms become separated or far enough apart on the agar surface to be distinguished. This will form visible colonies of each organism which will be isolated from the other colonies present. b) Flame the inoculation loop before each transfer to avoid contamination. c) Using the inoculation loop, aseptically “pick off” the......

Words: 933 - Pages: 4

Staining Microorganisms

...Staining Microorganisms Microorganisms are often first observed by coloring the specimen with a dye to emphasize the structures for examination. In order to dye, (or stain ) the specimen, it is fixed, (attached to the microscope slide). ( Tortara, Funke, Case, 2013). To carry through this staining and fixing, the microorganisms are killed and attached to the slide. There are several staining techniques to accomplish this preparation. There are simple stains, differential stains, and special stains. The stain is cationic (basic) or anionic (acidic). Examples of cationic dyes are crystal violet, safranin , methylene blue and basic fuchsin. Examples of anionic dye are, acid fuschin, congo red and nigrosin. Simple stains are, as they are called, “simple”; they are an alcohol solution of a basic dye, and they will highlight the microorganism so the observer can examine the structures , arrangements of cells, and shape of the specimen. If needed, an additive mordant) can be added to the sample to thicken it, making it easier to see. Simple stains are the least expensive method of staining, and can be used with all microorganisms. These are effective because they stain a pure culture and do not have to be washed and re stained. Differential stains are the most widely used staining technique for examining bacteria, as the stains react differently with different cell typed. This method of staining uses the Gram stain and the acid-fast stain. Gram staining is......

Words: 558 - Pages: 3

Diagnosing an Microorganisms Using Stains

...You start with a heat fixed smear. Fixing a slide kills the microorganism. A thin film of the microorganism is put on the slid and allowed to dry. Once dried, it is then fixed by either being passed through the flame of a Bunson burner several times or covered with methyl alcohol for 1 minute. Malachite green is applied and the smear is heated to steaming for 5 minutes, helping the stain penetrate the endospore wall. It is then washed with water for 30 seconds. This removes the stain from the cell except for the endospore wall. Safranin is applied as a counterstain to stain portions of the cell other than the endospore. In the smear, the endospores appear green with the rest of the cell red or pink. If there no endospores in the smear, it would eliminate bacillus as a contributing factor. Escherichia, commonly called E-coli, are also rod shaped microorganisms, and are gram negative. A gram stain is a differential stain developed Danish bacteriologist Hans Christian Gram. You start with a heat fixed smear using the procedure stated above. After they are fixed, it is then covered with crystal violet (or basic purple dye). After a short time, the dye is washed off and the smear is covered with iodine, which is a mordant. A mordant is a chemical additive to intensify the stain. The iodine is then washed off. At this point, both gram positive and gram negative microorganisms are violet. To determine if the microorganism is gram positive, the slide is washed with alcohol,......

Words: 677 - Pages: 3

Microbial Growth

...Brittney Guzman Anthony Spencer Tifuh, Nkweti Emmanuel Duodu, Amanda Boiter Microbial Growth on Lunchmeat Increases Over Time at Room Temperature Abstract Lunchmeat is a perfect medium for the rapid growth of microbes because it is high in moisture. How long can zip locked lunchmeat be left out before it becomes unsafe for consumption? In order to test the safety of lunchmeat being left out of refrigeration, an experiment was conducted over a three-day period. All turkey samples were in a zip locked bag, the 24 and 72 hour samples were left out at room temperature; the control remained refrigerated. All samples were inoculated into agar deeps, then into petri dishes to create a series of dilutions. We observed growth on all three Petri Dishes with the control having the least and 72-hour containing the most. This shows that although the turkey meat was sealed, microbial growth increases over time while left out at room temperature. This is important to maintain and know the safety of ingestion of lunchmeat after 24-72 hours. Introduction “Refrigerated storage is now one of the most widely practiced methods of controlling microbial growth in perishable foods. As a result of this practice, refrigerated storage of perishable foods has been shown to be a potential risk factor for the development of microbial hazards leading to foodborne illness”(Simon). Food poisoning is very common and in order to avoid this illness certain precautions need to be maintained to prevent this.......

Words: 1089 - Pages: 5

Temperature: Effects on Growth

...Temperature: Effects on Growth Scientists have discovered that microorganisms grow on a broad temperature range from 0 degrees to more than 100 degrees. There are four groups that help classify their most favorable development. 1. Psychrophiles are when the most favorable development is between -5 degrees and 20 degrees. They are mostly found in artic areas. 2. Mesophiles are when the most favorable development is between 20 degrees and 50 degrees. This class is where most of the bacteria development occurs. 3. Thermophiles are when the most favorable development is between 50 degrees and 80 degrees. It is here that you ill find growth in compost piles where fermentation can occur. 4. Hyperthermophiles are when the most favorable development is when the temperature exceeds 80 degrees. They are mostly found in volcanic areas and hot springs. (Brown, 2007, p 181) The microorganisms will grow in one of the four groups; they will not continue to develop into the other groups (Brown, 2007, p 181). Brown states that during this experiment we will attempt to measure the effects of various temperatures on pigment production and growth rate 2007, p 181). With this test there are three cellular components that are involved in metabolism that are influenced by temperature, they are cell membrane, ribosomes, and DNA. Those three cellular components are going to play a key role in the experiment. I believe that the Escherichia coli will have the......

Words: 674 - Pages: 3

Microorganisms

...In this essay I will be analysing micro organisms and disease. Firstly I will be defining micro organisms and then explaining the key features of the main categories of microorganisms. Followed by the roles of commensals and pathogens I will then go on to explain how micro organisms are transmitted and the routes of entry to and exit from the human body of micro organisms. I will also be explaining the logical sequence of events that occur from entry of a micro-organism to the body to the appearance of symptoms of a disease and then go onto discuss why not all infections lead to a disease. Finally I will explain a logical sequence the signs, symptoms and treatments of yellow fever which is an infectious disease. Micro organisms are living organisms (such as bacteria, fungi, viruses) which are too small to even be seen with the naked eye but visible under a microscope also named microbe. There are five types of living micro organisms these are bacteria, viruses, fungi, protozoa and algae. Microorganisms are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six major types: bacteria, archaea, fungi, protozoa, algae, and viruses. Bacteria are unicellular organisms. The cells are described as prokaryotic because they lack a nucleus. They exist in four major shapes: bacillus (rod shape), coccus (spherical shape), spirilla (spiral shape), and vibrio (curved shape). Most bacteria have a peptidoglycan cell wall they......

Words: 1792 - Pages: 8

The Growth and Characterisation of Bacterial Biofilm Underflow.

...Sulphate-Reducing Bacteria Tryptone soya Agar Tryptone soya Broth Ug Microgram Ul Microlitre Abstract Biofilms are gainful to people as microflora colonizing surfaces of the human body. This research is to study the growth and characteristics of biofilm underflow. These biofilms additionally frame an essential piece of numerous biotechnologies, including mechanical generation and sewage water treatment. Comprehension of the biofilm structure can add to understanding the biofilm development and fundamental biochemical instruments hidden this procedure. It may help to grow more proficient treatment systems for biofilm contaminations. The Objectives of this thesis is to research the advancement of mutational resistances to anti-microbial in pseudomonas aeruginosa, E.coli and Cronobacter biofilms in flow system. And the methods broadly suggest about, Mutation frequencies to resistance against cipirofloxacin and rifampicin were resolved for planktonic culture and in biofilm cultures generated by growth in a flow system. More over the results stress the variability of biofilm societies expanded for, respectively, compared with planktonic cultures. Pseudomonas strains are highly resistant to ciprofloxacin (150µl (3mg) which is suitable for its growth and this also it give numerous colonies. But in the case of Cronobacter and E.coli 25µl (.5mg) is enough to give colonies after 48 hrs. With the use of rifampicin, E.coli and Cronobacter give colonies......

Words: 14532 - Pages: 59

Microbiology Lab-Bacterial Growth and Controlling It

...A. Describe the difference between an obligate and facultative aerobe. Obligate aerobes are bacteria that require oxygen for growth. They will only grow at the top portion of the culture media where it meets the air and has a lot of oxygen. Facultative aerobes grow based on what is available to it. They prefer oxygen but oxygen is not necessary for growth. These aerobes mainly cluster at the top of the culture media where they have a high concentration of oxygen but will dispersed throughout because they do not require oxygen. B. Discuss the temperature requirements of the organisms in this lab. 1. Explain what type of organisms they are. Staphylococcus epidermis and Lactobacillus acidophilus are both a bacteria microbe. They grow best at normal body temperature, close to 370C. Microorganisms are classified according to their preferred temperature ranges. Because both grew at 370C, they would be classified as mesophiles. Mesophiles grow best in moderate temperatures ranging between 250C – 450C (Alonzo, n.d.). C. Discuss under what conditions you would want to control the growth of microbes. 1. Explain what type of control you would employ in each situation. To minimize the risk of contamination from unwanted organisms, aseptic technique is required. In this experiment I washed my hands with antibacterial soap. I then place on gloves to prevent contamination to the cultures from the bacteria on my skin and to protect myself from unintended exposure of......

Words: 1328 - Pages: 6

Growth

...Personal Growth Plan Planning your personal growth goals, not a new concept but an important one to map out. Personal growth enables us to develop, to reach our full potential. Growing as a person is never easy, because it requires change. We as humans naturally get into a comfort zone and the only way to grow is to leave that comfort zone. The six growth goals of mines in no particular order would be: 1. Better public speaker, 2. getting healthier, 3. more outgoing, 4. better body language, and 5. accept changes, and 6. ignore negative situations. These six growth goals would help me become a better person, and complete me as a well rounded individual. Graduating in May, with an interest in the business world I know I have to become a better public speaker. Public speaking doesn't come naturally for me, but I must improve. First, goal of action is to volunteer now with events that would force me to speak. Then I could speak on topics that I am interested in. I feel as if I'm passionate about the topic, speaking about will be easier. I'll practice and prepare before every speech, to make sure I get the kinks out the way. I don't have a full list of classes left to take, so I can a public speaking course. Lastly, join a group such as toastmasters or something similar. My attended timeline for these actions would be a year from now. If I put effort into these plans on becoming a better public speaker, I will become one in due time. My personal and mental health is very...

Words: 956 - Pages: 4

Isolation of Microorganisms from Evironmental Samples

...University of Santo Tomas College of Science Isolation of Microorganisms from Environmental Samples Experiment 6 (Group 6) JALIPA, Jomari T. JAVIER, Rhea A. JIMENEZ, Ma. Mikaela P. JURILLA, Joaquim Gerardo L. March 2016 ABSTRACT The exercise aims to enumerate the various microbial species that are present in a particular environment by collecting different substances such as pond water and soil that will be the source of microorganisms to be isolated and identified. Moreover, this exercise also aims to isolate microorganisms from the environment. This will be done by exposing half-strength Nutrient Agar plates to a specific site the experimenters chose. After which, the Agar plate will be incubated and the colonies formed were observed in the laboratory. INTRODUCTION There are approximately 10,000 named species of microorganisms. It is estimated that there are between 10,000 and 100,000 more unidentified species for every identified one (Truckee Meadows Community College, n.d.). Upon appearance, these microbes have evolved, diversified and virtually occupied every habitat possible on earth; from extreme environments to the corners of our nails, or from the deepest parts of the ocean to the tip of the high mountains. The ubiquity of these microorganisms causes them to populate in natural environments whether suspended in air, in water or associated with other organisms (ie: humans). Different surfaces whether inside or outside...

Words: 1518 - Pages: 7

Growth

...Macro Assignment Tahirah Smith- 409002047 Question 1 Consider the following between the real money supply and the growth rate of money: Δ(M/P) /M/P=-γu where M is the money supply, P is the price level, γ is a constant of proportionality and u is the constant growth rate of money. a) The relationship measures the sensitivity of real money balances to the growth rate of money. The equation shows that the growth rate of money is inversely related to the real money supply, i.e. if the growth rate of money increases, the level of real money supply will fall. b) The price level is proportional to the money supply and to hold the growth rate of money constant the price level will have to increase in proportion to an increase money supply or fall in proportion to a fall in money supply. c) If the growth rate of money increases while holding the money supply constant, the price level will have to rise since overall real money balances need to fall. d) If the growth rate of money is reduced, the central bank would have to increase the money supply if they also wish to hold the price level constant. Question2 a) Nominal value of government interest payments = nominal interest rate × initial debt Country A: Country B: 0.07 × $2,000 0.02 × $2,000 = $140 = $40 b) Official government deficits = Revenue – Government spending – Nominal interest payments Country A: Country B: $340 - $200 - $140 $340 - $200 - $40 ...

Words: 1266 - Pages: 6

Scooby-Doo! and the Gourmet Ghost | Hello Neighbor | Sandy Baron