Description
Match the following
1. sea star
2. sea urchins
3. sand dollars
4.brittle stars
A) bilateral flattened
B) five arms attached to central region
C)Radial oval test
D)fiive arms attached to a round central disk
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Explanation & Answer
1..........B
2.....................A
3...........................D
4............................C
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Glendale Community College Enviromental Science Essay
THE ASSIGNMENT:This assignment challenges you to put together many of the key concepts we've covered in this class in unit ...
Glendale Community College Enviromental Science Essay
THE ASSIGNMENT:This assignment challenges you to put together many of the key concepts we've covered in this class in units 1 and 2, and to successfully apply them, using a bit of imagination. Read the directions below, and write your answer. Turn in your answer as a .doc, .docx, or .pdf file. Double-space your answer.(By the way, this assignment is where you test yourself to see if you've really mastered the ideas you need to have mastered up to this point in the course. I'm checking to see that. It's not an assignment to be done in a hurry. So, if you're unsure about any of the concepts involved, this is the time to go back and really work on getting them before you complete the assignment. That's what this assignment is for!)DETAILS:Imagine that there is a kind of animal called a "critter." At first, there is only one species of critter. For this writing assignment, your job is to describe how that one species evolves into two separate species that have several important traits that differ from each other.Your description must make use of the following concepts, identifying each one by NAME, EXPLAINING what each concept means, and APPLYING the concept to the story of how the one species of critter evolved into two, separate species:
ecological niche
genetic mutation
reproductive isolation
natural selection
fitness
genetic drift
You are not required to use the concepts in the order listed above. However, by the end of your description it should be clear how the evolution occurred, how each of these concepts was involved in the process, and how the resulting two species differ from each other as a result of this evolutionary process.Please examine the GRADING RUBRIC (below) to see how your answer will be evaluated. Note how it requires each concept to be NAMED, each one to be fully EXPLAINED, and each one to be APPLIED to the evolution of the critter into two separate species.ANSWER LENGTH:There is no official minimum length. However, if your answer is less than about 350 words, I suggest that you have not written enough to answer the question thoroughly, to really show you know the concepts in question – and you probably want to shoot for more than the bare minimum if you’re trying for a high score! (I tried answering this question myself. My answer was 420 words long. It was about one and a half pages, double-spaced.)TIPS and REMINDERS:
Don't forget that separate species will not evolve without reproductive isolation occurring first! So, you'll probably want to have the population of critters divided into two near the beginning of your paper. How that happens is up to you. Remember, reproductive isolation does not need to take place in one, sudden moment. It can develop slowly.
Once you have two separate populations, the environment that each one lives in can begin to diverge from each other (different climate? different food sources? different predators? etc). This would lead to each population evolving a somewhat different niche. You can show you understand the connection between natural selection and the way traits evolve to be adapted to a particular niche.
When you talk about genetic mutation, make sure to give some details about what this means in terms of things like gametes and DNA.
Remember that whenever a trait becomes more common or less common in a population because having that traits helps or hurts fitness, this is a matter of natural selection, not genetic drift. "Genetic drift" refers only to situations in which a trait becomes more common or less common over time completely due to random chance, having nothing to do with the value of the trait itself.
Remember that evolution can take place over LONG periods of time. Don't try to have your two species evolve in the span of a generation or a few generations. Similarly, if you're going to have the environment a population lives in change over time, and have the population evolve to adapt to it, you'll probably want to have that environment change SLOWLY, giving the population time to adapt through evolution. If the environment changes rapidly and in extreme ways, the population is more likely to just die off and go extinct before it has enough time to evolve successful adaptations!
5 pages
Geometric Properties Of Light
I. Introduction. In this experiment, the geometric properties of light will be observed by using a D-shaped lens, a ray ta ...
Geometric Properties Of Light
I. Introduction. In this experiment, the geometric properties of light will be observed by using a D-shaped lens, a ray table, and a light source from ...
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Acid Base Titration Lab
Titrations provide a method of quantitatively measuring the concentration of an unknown solution. In an acid-base titratio ...
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All work must be well-written and organized. If you need to organize your thoughts, please use a separate sheet of paper. ...
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Maricopa Community Colleges Microbiology Lab Report
Background Information
This lab will examine current methods of controlling microbial growth with special attention focuse ...
Maricopa Community Colleges Microbiology Lab Report
Background Information
This lab will examine current methods of controlling microbial growth with special attention focused on the use of heat, antibiotics, and hand washing.
Temperature
The use of extreme temperature to control the growth of microbes is common. Generally, if heat is applied, microbes are killed; if cold temperatures are used, microbial growth is inhibited.
Heat can be applied as dry or moist heat. Dry heat, such as that in hot air ovens or incinerators, denatures enzymes, dehydrates microbes, and kills by oxidation effects. A standard application of dry heat in a hot air oven is 170 ºC for 2 hours. One of the simplest methods of dry heat sterilization is direct flaming. Incineration, exposing contaminated materials to a direct flame, is a microbicidal technique. This procedure is used many times in the microbiology laboratory in order to sterilize inoculating loops.
a) Flaming a loop is a common aseptic technique used to incinerate any microorganisms on the loop. (modification of work by Anh-Hue Tu) b) A bactericinerator may be used to avoid an open flame in the laboratory. (modification of work by Brian Forster)
Creative Commons (opens in a new tab)https://openstax.org/books/microbiology/pages/13-2... (opens in a new tab) is licensed under CC BY 4.0 (opens in a new tab).
Dry heat is not the most effective way to kill microorganisms, however.
Moisture transfers heat energy to the microbial cell more efficiently than dry air, resulting in the denaturation of enzymes. Moist heat methods include pasteurization, boiling, and autoclaving.
In pasteurization, the temperature is maintained at 63 ºC for 30 min to kill designated organisms that are pathogenic or cause spoilage. This has many food applications, such as the processing of milk for human consumption.
Boiling (100 ºC) for 10 min will kill vegetative bacterial cells; however, endospores are not inactivated.
The most effective method of moist heat sterilization is autoclaving, the use of steam under pressure. Increased pressure raises the boiling point of water and produces steam with a higher temperature. Free-flowing steam under pressure requires the use of an autoclave, a double-walled metal vessel that allows steam to be pressurized in the outer jacket. At a designated pressure, the saturated steam is released into the inner chamber, from which all the air has been evacuated. The steam under pressure in the vacuumed inner chamber is now capable of achieving temperatures in excess of 100 ºC. Standard conditions for autoclaving are 15 psi and 121 ºC for 15 min. Autoclaving is microbicidal. This is usually sufficient to kill endospores and render material sterile.
a) Diagram of the internal autoclave mechanism (modification of work by Courtney Harrington) b) Programing an autoclave (modification of work by Lackemeyer MG, Kok-Mercado Fd, Wada J, Bollinger L, Kindrachuk J, Wahl-Jensen V, Kuhn JH, Jahrling PB)
There are two different methods of measuring heat effectiveness. Thermal death time is the length of time required to kill all bacteria in a liquid culture at a given temperature. The less common thermal death point is the temperature required to kill all bacteria in a liquid culture in 10 min. Thermal death time measures the amount of time it takes to kill the microorganisms, while thermal death point measures the temperature that is required to kill the microorganisms.
Antimicrobial Agents
The use of heat to control microorganisms is used most often for laboratory equipment and the surrounding environment. However, to control microorganisms in a human, heat cannot be used. A variety of chemicals called antimicrobial agents are available for controlling the growth of microbes.
Disinfectants are chemical agents used on inanimate objects to lower the level of microbes on their surface. Antiseptics are chemicals used on living tissue to decrease the number of microbes. Those that result in microbial death are called bactericidal agents. Those causing temporary inhibition of growth are bacteriostatic agents.
When the body's normal defense cannot prevent or overcome a disease, it is often treated with chemotherapy, such as antimicrobial drugs. An antibiotic is a substance produced by microorganisms that in small amounts inhibits another microorganism. Antibiotics are selective in their action, which means they kill or inhibit bacterial cells only. For this reason, antibiotics can be introduced into the body to treat bacterial infection without harming human cells.
The microbiology laboratory isolates pathogens and determines their sensitivity to chemotherapeutic agents. In evaluating the effectiveness of antimicrobial agents, the important criteria include the concentration, the length of contact, and the degree to which the agents are lethal or inhibiting. The disk-diffusion method is used to evaluate the effectiveness of a chemical agent. The Kirby-Bauer test for agar diffusion is the most commonly used disk-diffusion test. This test uses Mueller-Hinton agar, which allows the chemotherapeutic agent to diffuse freely through the agar.
In any disk-diffusion method, a Petri plate containing an agar growth medium is inoculated uniformly over its entire surface with the bacterium being studied. Paper disks impregnated with various chemotherapeutic agents are placed on the surface of the agar. During incubation of the bacterium on the agar, the chemotherapeutic agent diffuses from the disk from an area of high concentration to an area of lower concentration. After incubation, if the chemical is effective, a clear zone representing inhibition of growth can be seen around the disk. This clear zone is called the zone of inhibition. The larger the zone of inhibition, the more effective the chemotherapeutic agent is at inhibiting the bacterium.
Note though that disk-diffusion methods are not able to distinguish whether the inhibited bacteria were killed or if their growth was simply inhibited by the agent. To make such a determination, it would be necessary to inoculate from the zone of inhibition to grow a new culture. What result would indicate the agent is bactericidal, and what result would indicate that the agent is instead bacteriostatic?
The disk diffusion method
Creative Commons (opens in a new tab)https://openstax.org/books/microbiology/pages/13-4... (opens in a new tab) is licensed under CC BY 4.0 (opens in a new tab).
A disk-diffusion assay
Figure: A disk-diffusion assay is used to determine the effectiveness of chemical agents against a particular microbe.
A plate is inoculated with various antimicrobial discs. The zone of inhibition around each disc indicates how effective that antimicrobial is against the particular species being tested.
On these plates, four antimicrobial agents are tested for efficacy in killing Pseudomonas aeruginosa (left) and Staphylococcus aureus (right). These antimicrobials are much more effective at killing aureus, as indicated by the size of the zones of inhibition. (credit b: modification of work by American Society for Microbiology)
The diameter of the zone of inhibition can be measured. In general, the larger the zone, the more sensitive the microbe is to the antibiotic. The zone diameter is compared to a standard table for that particular drug and concentration. The organism is reported as sensitive, intermediate, or resistant. Physicians use this information to make decisions about which drugs to use in treating bacterial infections.
Hand Washing
Heat is used to kill microorganisms in the environment, and antibiotics are used to kill infections within the human body, but hand washing is the method that controls microorganisms ON the human body. Guidelines from the Centers for Disease Control and Prevention state that hand washing is the single most important procedure for preventing infections, yet (pre-2020 pandemic) studies in hospitals show the handwashing rate may be as low as 31%.
Commercial handwashing products containing antibacterial chemical agents are widely used in the home and workplace. Two types of products are available: hand soaps and ethyl alcohol-based hand gels. Hand soaps require the addition of water, while hand gels can be used without water.
To test the effectiveness of a particular handwashing product, an area of the hand is swabbed before and after hand washing. Bacteria on the swabs are transferred to an agar plate. After incubation, colonies on the plate are counted and the numbers used to calculate a percent decrease in bacteria. In the study depicted below, bacteria cultivated from the hand before and after washing with antibacterial hand soap have a 57% decrease. Bacteria cultivated from the hand gel before and after washing with an antibacterial hand gel have a 96% decrease.
Effectiveness of handwashing using hand soap versus hand gel
by Microbiology: A Photographic Atlas for the Laboratory
Washing with commercial handwashing products is the single most important physical measure for controlling and removing microorganisms.
How often do you wash your hands?
Laboratory Excercise Questions
~~1. Describe what the disk-diffusion method is and how the general process works. (4 points)
~~2. The disk-diffusion method was used to evaluate the effectiveness of three antibiotics on bacterial growth. The results were as follows:
AntibioticZone of inhibitionX30 mmY5 mmZ11 mm
a. Which antibiotic was the most effective against the microorganism? Why?
b. Based on these results, which antibiotic would you recommend for treatment of a disease caused by this bacterium? Why? (
c. How might you determine whether the effect of antibiotic Z in this experiment was bactericidal or bacteriostatic? Briefly explain what you would need to see to conclude that the effect was either bactericidal or bacteriostatic.
~~3. Indicators are used in autoclaving to ensure that sterilization is complete. One type of chemical indicator turns color when it has reached a specific temperature; the other type turns color when it has reached a specified temperature and been exposed to steam. Which type of indicator should be used and why?
~~4. What does the zone of inhibition represent? What factors influence the size of the zone?
~~5. The data below was collected from soaps after one week of use at a hospital nurses' hand washing station. Data are expressed as percentage of soap products contaminated. What conclusions can you draw from these data? Why? (5 points)
Type of OrganismsBar SoapScrew Top Liquid SoapSlit Top Flip Liquid SoapFlip & Pump Liquid SoapPump Liquid SoapTotal Bacteria95%71%39%10%0%Gram-positive cocci83%70%38%9%0%Gram-negative rods12%1%1%1%0%
Application Question
~~6. How might the information gained from this lab pertaining to the control of microorganisms be useful to you as a healthcare professional? (
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Glendale Community College Enviromental Science Essay
THE ASSIGNMENT:This assignment challenges you to put together many of the key concepts we've covered in this class in unit ...
Glendale Community College Enviromental Science Essay
THE ASSIGNMENT:This assignment challenges you to put together many of the key concepts we've covered in this class in units 1 and 2, and to successfully apply them, using a bit of imagination. Read the directions below, and write your answer. Turn in your answer as a .doc, .docx, or .pdf file. Double-space your answer.(By the way, this assignment is where you test yourself to see if you've really mastered the ideas you need to have mastered up to this point in the course. I'm checking to see that. It's not an assignment to be done in a hurry. So, if you're unsure about any of the concepts involved, this is the time to go back and really work on getting them before you complete the assignment. That's what this assignment is for!)DETAILS:Imagine that there is a kind of animal called a "critter." At first, there is only one species of critter. For this writing assignment, your job is to describe how that one species evolves into two separate species that have several important traits that differ from each other.Your description must make use of the following concepts, identifying each one by NAME, EXPLAINING what each concept means, and APPLYING the concept to the story of how the one species of critter evolved into two, separate species:
ecological niche
genetic mutation
reproductive isolation
natural selection
fitness
genetic drift
You are not required to use the concepts in the order listed above. However, by the end of your description it should be clear how the evolution occurred, how each of these concepts was involved in the process, and how the resulting two species differ from each other as a result of this evolutionary process.Please examine the GRADING RUBRIC (below) to see how your answer will be evaluated. Note how it requires each concept to be NAMED, each one to be fully EXPLAINED, and each one to be APPLIED to the evolution of the critter into two separate species.ANSWER LENGTH:There is no official minimum length. However, if your answer is less than about 350 words, I suggest that you have not written enough to answer the question thoroughly, to really show you know the concepts in question – and you probably want to shoot for more than the bare minimum if you’re trying for a high score! (I tried answering this question myself. My answer was 420 words long. It was about one and a half pages, double-spaced.)TIPS and REMINDERS:
Don't forget that separate species will not evolve without reproductive isolation occurring first! So, you'll probably want to have the population of critters divided into two near the beginning of your paper. How that happens is up to you. Remember, reproductive isolation does not need to take place in one, sudden moment. It can develop slowly.
Once you have two separate populations, the environment that each one lives in can begin to diverge from each other (different climate? different food sources? different predators? etc). This would lead to each population evolving a somewhat different niche. You can show you understand the connection between natural selection and the way traits evolve to be adapted to a particular niche.
When you talk about genetic mutation, make sure to give some details about what this means in terms of things like gametes and DNA.
Remember that whenever a trait becomes more common or less common in a population because having that traits helps or hurts fitness, this is a matter of natural selection, not genetic drift. "Genetic drift" refers only to situations in which a trait becomes more common or less common over time completely due to random chance, having nothing to do with the value of the trait itself.
Remember that evolution can take place over LONG periods of time. Don't try to have your two species evolve in the span of a generation or a few generations. Similarly, if you're going to have the environment a population lives in change over time, and have the population evolve to adapt to it, you'll probably want to have that environment change SLOWLY, giving the population time to adapt through evolution. If the environment changes rapidly and in extreme ways, the population is more likely to just die off and go extinct before it has enough time to evolve successful adaptations!
5 pages
Geometric Properties Of Light
I. Introduction. In this experiment, the geometric properties of light will be observed by using a D-shaped lens, a ray ta ...
Geometric Properties Of Light
I. Introduction. In this experiment, the geometric properties of light will be observed by using a D-shaped lens, a ray table, and a light source from ...
4 pages
Acid Base Titration Lab
Titrations provide a method of quantitatively measuring the concentration of an unknown solution. In an acid-base titratio ...
Acid Base Titration Lab
Titrations provide a method of quantitatively measuring the concentration of an unknown solution. In an acid-base titration, this is done by ...
5 pages
Assignment 4
All work must be well-written and organized. If you need to organize your thoughts, please use a separate sheet of paper. ...
Assignment 4
All work must be well-written and organized. If you need to organize your thoughts, please use a separate sheet of paper. A major objective of
Maricopa Community Colleges Microbiology Lab Report
Background Information
This lab will examine current methods of controlling microbial growth with special attention focuse ...
Maricopa Community Colleges Microbiology Lab Report
Background Information
This lab will examine current methods of controlling microbial growth with special attention focused on the use of heat, antibiotics, and hand washing.
Temperature
The use of extreme temperature to control the growth of microbes is common. Generally, if heat is applied, microbes are killed; if cold temperatures are used, microbial growth is inhibited.
Heat can be applied as dry or moist heat. Dry heat, such as that in hot air ovens or incinerators, denatures enzymes, dehydrates microbes, and kills by oxidation effects. A standard application of dry heat in a hot air oven is 170 ºC for 2 hours. One of the simplest methods of dry heat sterilization is direct flaming. Incineration, exposing contaminated materials to a direct flame, is a microbicidal technique. This procedure is used many times in the microbiology laboratory in order to sterilize inoculating loops.
a) Flaming a loop is a common aseptic technique used to incinerate any microorganisms on the loop. (modification of work by Anh-Hue Tu) b) A bactericinerator may be used to avoid an open flame in the laboratory. (modification of work by Brian Forster)
Creative Commons (opens in a new tab)https://openstax.org/books/microbiology/pages/13-2... (opens in a new tab) is licensed under CC BY 4.0 (opens in a new tab).
Dry heat is not the most effective way to kill microorganisms, however.
Moisture transfers heat energy to the microbial cell more efficiently than dry air, resulting in the denaturation of enzymes. Moist heat methods include pasteurization, boiling, and autoclaving.
In pasteurization, the temperature is maintained at 63 ºC for 30 min to kill designated organisms that are pathogenic or cause spoilage. This has many food applications, such as the processing of milk for human consumption.
Boiling (100 ºC) for 10 min will kill vegetative bacterial cells; however, endospores are not inactivated.
The most effective method of moist heat sterilization is autoclaving, the use of steam under pressure. Increased pressure raises the boiling point of water and produces steam with a higher temperature. Free-flowing steam under pressure requires the use of an autoclave, a double-walled metal vessel that allows steam to be pressurized in the outer jacket. At a designated pressure, the saturated steam is released into the inner chamber, from which all the air has been evacuated. The steam under pressure in the vacuumed inner chamber is now capable of achieving temperatures in excess of 100 ºC. Standard conditions for autoclaving are 15 psi and 121 ºC for 15 min. Autoclaving is microbicidal. This is usually sufficient to kill endospores and render material sterile.
a) Diagram of the internal autoclave mechanism (modification of work by Courtney Harrington) b) Programing an autoclave (modification of work by Lackemeyer MG, Kok-Mercado Fd, Wada J, Bollinger L, Kindrachuk J, Wahl-Jensen V, Kuhn JH, Jahrling PB)
There are two different methods of measuring heat effectiveness. Thermal death time is the length of time required to kill all bacteria in a liquid culture at a given temperature. The less common thermal death point is the temperature required to kill all bacteria in a liquid culture in 10 min. Thermal death time measures the amount of time it takes to kill the microorganisms, while thermal death point measures the temperature that is required to kill the microorganisms.
Antimicrobial Agents
The use of heat to control microorganisms is used most often for laboratory equipment and the surrounding environment. However, to control microorganisms in a human, heat cannot be used. A variety of chemicals called antimicrobial agents are available for controlling the growth of microbes.
Disinfectants are chemical agents used on inanimate objects to lower the level of microbes on their surface. Antiseptics are chemicals used on living tissue to decrease the number of microbes. Those that result in microbial death are called bactericidal agents. Those causing temporary inhibition of growth are bacteriostatic agents.
When the body's normal defense cannot prevent or overcome a disease, it is often treated with chemotherapy, such as antimicrobial drugs. An antibiotic is a substance produced by microorganisms that in small amounts inhibits another microorganism. Antibiotics are selective in their action, which means they kill or inhibit bacterial cells only. For this reason, antibiotics can be introduced into the body to treat bacterial infection without harming human cells.
The microbiology laboratory isolates pathogens and determines their sensitivity to chemotherapeutic agents. In evaluating the effectiveness of antimicrobial agents, the important criteria include the concentration, the length of contact, and the degree to which the agents are lethal or inhibiting. The disk-diffusion method is used to evaluate the effectiveness of a chemical agent. The Kirby-Bauer test for agar diffusion is the most commonly used disk-diffusion test. This test uses Mueller-Hinton agar, which allows the chemotherapeutic agent to diffuse freely through the agar.
In any disk-diffusion method, a Petri plate containing an agar growth medium is inoculated uniformly over its entire surface with the bacterium being studied. Paper disks impregnated with various chemotherapeutic agents are placed on the surface of the agar. During incubation of the bacterium on the agar, the chemotherapeutic agent diffuses from the disk from an area of high concentration to an area of lower concentration. After incubation, if the chemical is effective, a clear zone representing inhibition of growth can be seen around the disk. This clear zone is called the zone of inhibition. The larger the zone of inhibition, the more effective the chemotherapeutic agent is at inhibiting the bacterium.
Note though that disk-diffusion methods are not able to distinguish whether the inhibited bacteria were killed or if their growth was simply inhibited by the agent. To make such a determination, it would be necessary to inoculate from the zone of inhibition to grow a new culture. What result would indicate the agent is bactericidal, and what result would indicate that the agent is instead bacteriostatic?
The disk diffusion method
Creative Commons (opens in a new tab)https://openstax.org/books/microbiology/pages/13-4... (opens in a new tab) is licensed under CC BY 4.0 (opens in a new tab).
A disk-diffusion assay
Figure: A disk-diffusion assay is used to determine the effectiveness of chemical agents against a particular microbe.
A plate is inoculated with various antimicrobial discs. The zone of inhibition around each disc indicates how effective that antimicrobial is against the particular species being tested.
On these plates, four antimicrobial agents are tested for efficacy in killing Pseudomonas aeruginosa (left) and Staphylococcus aureus (right). These antimicrobials are much more effective at killing aureus, as indicated by the size of the zones of inhibition. (credit b: modification of work by American Society for Microbiology)
The diameter of the zone of inhibition can be measured. In general, the larger the zone, the more sensitive the microbe is to the antibiotic. The zone diameter is compared to a standard table for that particular drug and concentration. The organism is reported as sensitive, intermediate, or resistant. Physicians use this information to make decisions about which drugs to use in treating bacterial infections.
Hand Washing
Heat is used to kill microorganisms in the environment, and antibiotics are used to kill infections within the human body, but hand washing is the method that controls microorganisms ON the human body. Guidelines from the Centers for Disease Control and Prevention state that hand washing is the single most important procedure for preventing infections, yet (pre-2020 pandemic) studies in hospitals show the handwashing rate may be as low as 31%.
Commercial handwashing products containing antibacterial chemical agents are widely used in the home and workplace. Two types of products are available: hand soaps and ethyl alcohol-based hand gels. Hand soaps require the addition of water, while hand gels can be used without water.
To test the effectiveness of a particular handwashing product, an area of the hand is swabbed before and after hand washing. Bacteria on the swabs are transferred to an agar plate. After incubation, colonies on the plate are counted and the numbers used to calculate a percent decrease in bacteria. In the study depicted below, bacteria cultivated from the hand before and after washing with antibacterial hand soap have a 57% decrease. Bacteria cultivated from the hand gel before and after washing with an antibacterial hand gel have a 96% decrease.
Effectiveness of handwashing using hand soap versus hand gel
by Microbiology: A Photographic Atlas for the Laboratory
Washing with commercial handwashing products is the single most important physical measure for controlling and removing microorganisms.
How often do you wash your hands?
Laboratory Excercise Questions
~~1. Describe what the disk-diffusion method is and how the general process works. (4 points)
~~2. The disk-diffusion method was used to evaluate the effectiveness of three antibiotics on bacterial growth. The results were as follows:
AntibioticZone of inhibitionX30 mmY5 mmZ11 mm
a. Which antibiotic was the most effective against the microorganism? Why?
b. Based on these results, which antibiotic would you recommend for treatment of a disease caused by this bacterium? Why? (
c. How might you determine whether the effect of antibiotic Z in this experiment was bactericidal or bacteriostatic? Briefly explain what you would need to see to conclude that the effect was either bactericidal or bacteriostatic.
~~3. Indicators are used in autoclaving to ensure that sterilization is complete. One type of chemical indicator turns color when it has reached a specific temperature; the other type turns color when it has reached a specified temperature and been exposed to steam. Which type of indicator should be used and why?
~~4. What does the zone of inhibition represent? What factors influence the size of the zone?
~~5. The data below was collected from soaps after one week of use at a hospital nurses' hand washing station. Data are expressed as percentage of soap products contaminated. What conclusions can you draw from these data? Why? (5 points)
Type of OrganismsBar SoapScrew Top Liquid SoapSlit Top Flip Liquid SoapFlip & Pump Liquid SoapPump Liquid SoapTotal Bacteria95%71%39%10%0%Gram-positive cocci83%70%38%9%0%Gram-negative rods12%1%1%1%0%
Application Question
~~6. How might the information gained from this lab pertaining to the control of microorganisms be useful to you as a healthcare professional? (
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